<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.5c -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Cover" roleURI="http://ir.viomi.com/role/Cover" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#BalanceSheetsUnaudited" roleURI="http://ir.viomi.com/role/BalanceSheetsUnaudited" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#BalanceSheetsUnauditedParenthetical" roleURI="http://ir.viomi.com/role/BalanceSheetsUnauditedParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#StatementsOfComprehensiveIncomeLossUnaudited" roleURI="http://ir.viomi.com/role/StatementsOfComprehensiveIncomeLossUnaudited" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#StatementsOfChangesInShareholdersEquityUnaudited" roleURI="http://ir.viomi.com/role/StatementsOfChangesInShareholdersEquityUnaudited" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#StatementsOfCashFlowsUnaudited" roleURI="http://ir.viomi.com/role/StatementsOfCashFlowsUnaudited" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#OrganizationAndPrincipalActivities" roleURI="http://ir.viomi.com/role/OrganizationAndPrincipalActivities" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SignificantAccountingPolicies" roleURI="http://ir.viomi.com/role/SignificantAccountingPolicies" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ConcentrationAndRisks" roleURI="http://ir.viomi.com/role/ConcentrationAndRisks" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#CashAndCashEquivalents" roleURI="http://ir.viomi.com/role/CashAndCashEquivalents" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RestrictedCash" roleURI="http://ir.viomi.com/role/RestrictedCash" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Short-termInvestments" roleURI="http://ir.viomi.com/role/Short-termInvestments" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#InventoriesNet" roleURI="http://ir.viomi.com/role/InventoriesNet" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#PrepaidExpensesAndOtherAssets" roleURI="http://ir.viomi.com/role/PrepaidExpensesAndOtherAssets" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#PropertyPlantAndEquipmentNet" roleURI="http://ir.viomi.com/role/PropertyPlantAndEquipmentNet" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#LandUseRightNet" roleURI="http://ir.viomi.com/role/LandUseRightNet" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Borrowings" roleURI="http://ir.viomi.com/role/Borrowings" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#AccruedExpensesAndOtherLiabilities" roleURI="http://ir.viomi.com/role/AccruedExpensesAndOtherLiabilities" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SegmentReporting" roleURI="http://ir.viomi.com/role/SegmentReporting" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Revenue" roleURI="http://ir.viomi.com/role/Revenue" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#IncomeTaxExpenses" roleURI="http://ir.viomi.com/role/IncomeTaxExpenses" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#OrdinaryShares" roleURI="http://ir.viomi.com/role/OrdinaryShares" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Share-basedCompensation" roleURI="http://ir.viomi.com/role/Share-basedCompensation" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#NetIncomeLossPerShare" roleURI="http://ir.viomi.com/role/NetIncomeLossPerShare" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RelatedPartyTransactions" roleURI="http://ir.viomi.com/role/RelatedPartyTransactions" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#FairValueMeasurements" roleURI="http://ir.viomi.com/role/FairValueMeasurements" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Leases" roleURI="http://ir.viomi.com/role/Leases" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#CommitmentsAndContingencies" roleURI="http://ir.viomi.com/role/CommitmentsAndContingencies" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RestrictedNetAssets" roleURI="http://ir.viomi.com/role/RestrictedNetAssets" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SubsequentEvent" roleURI="http://ir.viomi.com/role/SubsequentEvent" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#UnauditedCondensedFinancialInformationOfParentCompany" roleURI="http://ir.viomi.com/role/UnauditedCondensedFinancialInformationOfParentCompany" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SignificantAccountingPoliciesPolicies" roleURI="http://ir.viomi.com/role/SignificantAccountingPoliciesPolicies" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#OrganizationAndPrincipalActivitiesTables" roleURI="http://ir.viomi.com/role/OrganizationAndPrincipalActivitiesTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SignificantAccountingPoliciesTables" roleURI="http://ir.viomi.com/role/SignificantAccountingPoliciesTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ConcentrationAndRisksTables" roleURI="http://ir.viomi.com/role/ConcentrationAndRisksTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#CashAndCashEquivalentsTables" roleURI="http://ir.viomi.com/role/CashAndCashEquivalentsTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#InventoriesNetTables" roleURI="http://ir.viomi.com/role/InventoriesNetTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#PrepaidExpensesAndOtherAssetsTables" roleURI="http://ir.viomi.com/role/PrepaidExpensesAndOtherAssetsTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#PropertyPlantAndEquipmentNetTables" roleURI="http://ir.viomi.com/role/PropertyPlantAndEquipmentNetTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#LandUseRightNetTables" roleURI="http://ir.viomi.com/role/LandUseRightNetTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#BorrowingsTables" roleURI="http://ir.viomi.com/role/BorrowingsTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#AccruedExpensesAndOtherLiabilitiesTables" roleURI="http://ir.viomi.com/role/AccruedExpensesAndOtherLiabilitiesTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RevenueTables" roleURI="http://ir.viomi.com/role/RevenueTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#IncomeTaxExpensesTables" roleURI="http://ir.viomi.com/role/IncomeTaxExpensesTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Share-basedCompensationTables" roleURI="http://ir.viomi.com/role/Share-basedCompensationTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#NetIncomeLossPerShareTables" roleURI="http://ir.viomi.com/role/NetIncomeLossPerShareTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RelatedPartyTransactionsTables" roleURI="http://ir.viomi.com/role/RelatedPartyTransactionsTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#FairValueMeasurementsTables" roleURI="http://ir.viomi.com/role/FairValueMeasurementsTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#LeasesTables" roleURI="http://ir.viomi.com/role/LeasesTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#CommitmentsAndContingenciesTables" roleURI="http://ir.viomi.com/role/CommitmentsAndContingenciesTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#UnauditedCondensedFinancialInformationOfParentCompanyTables" roleURI="http://ir.viomi.com/role/UnauditedCondensedFinancialInformationOfParentCompanyTables" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfPrincipalSubsidiariesAndViesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfPrincipalSubsidiariesAndViesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfFinancialStatementAmountsAndBalancesOfViesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfFinancialStatementAmountsAndBalancesOfViesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfFinancialStatementAmountsAndBalancesOfViesDetailsParenthetical" roleURI="http://ir.viomi.com/role/ScheduleOfFinancialStatementAmountsAndBalancesOfViesDetailsParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#OrganizationAndPrincipalActivitiesDetailsNarrative" roleURI="http://ir.viomi.com/role/OrganizationAndPrincipalActivitiesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfActivityInAllowanceForCreditLossesRelatedToAccountsAndNotesReceivableAndOtherReceivablesFromRelatedPartiesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfActivityInAllowanceForCreditLossesRelatedToAccountsAndNotesReceivableAndOtherReceivablesFromRelatedPartiesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SignificantAccountingPoliciesDetailsNarrative" roleURI="http://ir.viomi.com/role/SignificantAccountingPoliciesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SignificantAccountingPoliciesDetailsNarrativeDefOnly" roleURI="http://ir.viomi.com/role/SignificantAccountingPoliciesDetailsNarrativeDefOnly" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfConcentrationOfRiskDetails" roleURI="http://ir.viomi.com/role/SummaryOfConcentrationOfRiskDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfCashAndCashEquivalentsDetails" roleURI="http://ir.viomi.com/role/SummaryOfCashAndCashEquivalentsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RestrictedCashDetailsNarrative" roleURI="http://ir.viomi.com/role/RestrictedCashDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Short-termInvestmentsDetailsNarrative" roleURI="http://ir.viomi.com/role/Short-termInvestmentsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfInventoriesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfInventoriesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#InventoriesNetDetailsNarrative" roleURI="http://ir.viomi.com/role/InventoriesNetDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfPrepaidExpensesAndOtherAssetsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfPrepaidExpensesAndOtherAssetsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfPropertyPlantAndEquipmentNetDetails" roleURI="http://ir.viomi.com/role/ScheduleOfPropertyPlantAndEquipmentNetDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#PropertyPlantAndEquipmentNetDetailsNarrative" roleURI="http://ir.viomi.com/role/PropertyPlantAndEquipmentNetDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfLandUseRightNetDetails" roleURI="http://ir.viomi.com/role/SummaryOfLandUseRightNetDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfEstimatedFutureAmortizationExpenseForLandUseRightsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfEstimatedFutureAmortizationExpenseForLandUseRightsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#LandUseRightNetDetailsNarrative" roleURI="http://ir.viomi.com/role/LandUseRightNetDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfShort-termBorrowingsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfShort-termBorrowingsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfShort-termBorrowingsDetailsParenthetical" roleURI="http://ir.viomi.com/role/ScheduleOfShort-termBorrowingsDetailsParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfLong-termBorrowingsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfLong-termBorrowingsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfFutureMaturitiesOfLong-termBorrowingsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfFutureMaturitiesOfLong-termBorrowingsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#BorrowingsDetailsNarrative" roleURI="http://ir.viomi.com/role/BorrowingsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfAccruedExpensesAndOtherLiabilitiesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfAccruedExpensesAndOtherLiabilitiesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfProductWarrantActivitiesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfProductWarrantActivitiesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SegmentReportingDetailsNarrative" roleURI="http://ir.viomi.com/role/SegmentReportingDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfRevenueDetails" roleURI="http://ir.viomi.com/role/ScheduleOfRevenueDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfCurrentAndDeferredComponentsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfCurrentAndDeferredComponentsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfReconciliationIncomeTaxExpensesDetails" roleURI="http://ir.viomi.com/role/ScheduleOfReconciliationIncomeTaxExpensesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfPerSharesEffectOfTaxDetails" roleURI="http://ir.viomi.com/role/ScheduleOfPerSharesEffectOfTaxDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfDeferredTaxAssetsDetails" roleURI="http://ir.viomi.com/role/ScheduleOfDeferredTaxAssetsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#ScheduleOfMovementOfValuationAllowanceDetails" roleURI="http://ir.viomi.com/role/ScheduleOfMovementOfValuationAllowanceDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#IncomeTaxExpensesDetailsNarrative" roleURI="http://ir.viomi.com/role/IncomeTaxExpensesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#OrdinarySharesDetailsNarrative" roleURI="http://ir.viomi.com/role/OrdinarySharesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfCompensationExpenseRecognizedForShare-basedAwardsDetails" roleURI="http://ir.viomi.com/role/SummaryOfCompensationExpenseRecognizedForShare-basedAwardsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfStockOptionActivityDetails" roleURI="http://ir.viomi.com/role/SummaryOfStockOptionActivityDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#Share-basedCompensationDetailsNarrative" roleURI="http://ir.viomi.com/role/Share-basedCompensationDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfNetIncomePerShareBasicAndDilutedDetails" roleURI="http://ir.viomi.com/role/SummaryOfNetIncomePerShareBasicAndDilutedDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfRelatedPartyTransactionRelationshipDetails" roleURI="http://ir.viomi.com/role/SummaryOfRelatedPartyTransactionRelationshipDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfRelatedPartyTransactionsDetails" roleURI="http://ir.viomi.com/role/SummaryOfRelatedPartyTransactionsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfAssetsMeasuredAtFairValueOnRecurringBasisDetails" roleURI="http://ir.viomi.com/role/SummaryOfAssetsMeasuredAtFairValueOnRecurringBasisDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfComponentsOfLeaseExpenseDetails" roleURI="http://ir.viomi.com/role/SummaryOfComponentsOfLeaseExpenseDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfSupplementalCashFlowInformationForLeasesDetails" roleURI="http://ir.viomi.com/role/SummaryOfSupplementalCashFlowInformationForLeasesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfAggregateFutureMinimumRentalPaymentsUnderNon-cancelableAgreementDetails" roleURI="http://ir.viomi.com/role/SummaryOfAggregateFutureMinimumRentalPaymentsUnderNon-cancelableAgreementDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#LeasesDetailsNarrative" roleURI="http://ir.viomi.com/role/LeasesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#SummaryOfCapitalAndOtherCommitmentDetails" roleURI="http://ir.viomi.com/role/SummaryOfCapitalAndOtherCommitmentDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#CommitmentsAndContingenciesDetailsNarrative" roleURI="http://ir.viomi.com/role/CommitmentsAndContingenciesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#RestrictedNetAssetsDetailsNarrative" roleURI="http://ir.viomi.com/role/RestrictedNetAssetsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#UnauditedCondensedParentCompanyBalanceSheetsDetails" roleURI="http://ir.viomi.com/role/UnauditedCondensedParentCompanyBalanceSheetsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#UnauditedCondensedParentCompanyBalanceSheetsParentheticalDetails" roleURI="http://ir.viomi.com/role/UnauditedCondensedParentCompanyBalanceSheetsParentheticalDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#UnauditedCondensedParentCompanyStatementsOfOperationsDetails" roleURI="http://ir.viomi.com/role/UnauditedCondensedParentCompanyStatementsOfOperationsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="viot-20260630.xsd#UnauditedCondensedParentCompanyStatementsOfCashFlowsDetails" roleURI="http://ir.viomi.com/role/UnauditedCondensedParentCompanyStatementsOfCashFlowsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-roles-2026.xsd#eedm1" roleURI="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#notAll" arcroleURI="http://xbrl.org/int/dim/arcrole/notAll" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Cover" xlink:title="00000001 - Document - Cover" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/BalanceSheetsUnaudited" xlink:title="00000002 - Statement - Condensed Consolidated Balance Sheets Unaudited">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonrelatedPartyMember" xlink:label="loc_us-gaapNonrelatedPartyMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapNonrelatedPartyMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember_60" xlink:type="arc" order="61" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaapCommonClassBMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassBMember_80" xlink:type="arc" order="81" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaapAssetsAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsAbstract_110" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaapAssetsCurrentAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_110" xlink:to="loc_us-gaapAssetsCurrentAbstract_110" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_110" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashCurrent" xlink:label="loc_us-gaapRestrictedCashCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapRestrictedCashCurrent_110" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ShortTermDeposit" xlink:label="loc_VIOTShortTermDeposit_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_VIOTShortTermDeposit_110" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermInvestments" xlink:label="loc_us-gaapShortTermInvestments_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapShortTermInvestments_110" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapAccountsReceivableNetCurrent_110" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_OtherReceivablesFromRelatedParties" xlink:label="loc_VIOTOtherReceivablesFromRelatedParties_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_VIOTOtherReceivablesFromRelatedParties_110" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapInventoryNet_110" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent_110" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaapAssetsCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_110" xlink:to="loc_us-gaapAssetsCurrent_110" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsNoncurrentAbstract" xlink:label="loc_us-gaapAssetsNoncurrentAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_110" xlink:to="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsNoncurrent" xlink:label="loc_us-gaapPrepaidExpenseAndOtherAssetsNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapPrepaidExpenseAndOtherAssetsNoncurrent_110" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet_110" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_LongtermDeposits" xlink:label="loc_VIOTLongtermDeposits_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_VIOTLongtermDeposits_110" xlink:type="arc" order="14" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="loc_us-gaapDeferredIncomeTaxAssetsNet_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapDeferredIncomeTaxAssetsNet_110" xlink:type="arc" order="15" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaapIntangibleAssetsNetExcludingGoodwill_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapIntangibleAssetsNetExcludingGoodwill_110" xlink:type="arc" order="16" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaapOperatingLeaseRightOfUseAsset_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapOperatingLeaseRightOfUseAsset_110" xlink:type="arc" order="17" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_LandUseRightsNet" xlink:label="loc_VIOTLandUseRightsNet_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_VIOTLandUseRightsNet_110" xlink:type="arc" order="18" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermInvestments" xlink:label="loc_us-gaapLongTermInvestments_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapLongTermInvestments_110" xlink:type="arc" order="19" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsNoncurrent" xlink:label="loc_us-gaapAssetsNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_110" xlink:to="loc_us-gaapAssetsNoncurrent_110" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssets_110" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaapLiabilitiesCurrentAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:type="arc" order="23" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapAccountsPayableCurrent_110" xlink:type="arc" order="24" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="loc_us-gaapContractWithCustomerLiabilityCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapContractWithCustomerLiabilityCurrent_110" xlink:type="arc" order="25" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapOtherLiabilitiesCurrent_110" xlink:type="arc" order="26" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AccruedLiabilitiesAndOtherLiabilitiesCurrent" xlink:label="loc_VIOTAccruedLiabilitiesAndOtherLiabilitiesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_VIOTAccruedLiabilitiesAndOtherLiabilitiesCurrent_110" xlink:type="arc" order="27" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermBorrowings" xlink:label="loc_us-gaapShortTermBorrowings_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapShortTermBorrowings_110" xlink:type="arc" order="28" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedIncomeTaxesCurrent" xlink:label="loc_us-gaapAccruedIncomeTaxesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapAccruedIncomeTaxesCurrent_110" xlink:type="arc" order="29" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapOperatingLeaseLiabilityCurrent_110" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaapLongTermDebtCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapLongTermDebtCurrent_110" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaapLiabilitiesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_110" xlink:to="loc_us-gaapLiabilitiesCurrent_110" xlink:type="arc" order="32" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrentAbstract" xlink:label="loc_us-gaapLiabilitiesNoncurrentAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapLiabilitiesNoncurrentAbstract_110" xlink:type="arc" order="33" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesNoncurrent" xlink:label="loc_us-gaapAccountsPayableAndAccruedLiabilitiesNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapAccountsPayableAndAccruedLiabilitiesNoncurrent_110" xlink:type="arc" order="34" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaapLongTermDebtNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapLongTermDebtNoncurrent_110" xlink:type="arc" order="35" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapOperatingLeaseLiabilityNoncurrent_110" xlink:type="arc" order="36" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrent" xlink:label="loc_us-gaapLiabilitiesNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapLiabilitiesNoncurrent_110" xlink:type="arc" order="37" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapLiabilities_110" xlink:type="arc" order="38" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaapCommitmentsAndContingencies_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapCommitmentsAndContingencies_110" xlink:type="arc" order="39" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xlink:label="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_110" xlink:to="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:type="arc" order="40" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapCommonStockValue_110" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValue" xlink:label="loc_us-gaapTreasuryStockValue_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapTreasuryStockValue_110" xlink:type="arc" order="42" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapAdditionalPaidInCapital_110" xlink:type="arc" order="43" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit_110" xlink:type="arc" order="44" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax_110" xlink:type="arc" order="45" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapStockholdersEquity_110" xlink:type="arc" order="46" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterest" xlink:label="loc_us-gaapMinorityInterest_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapMinorityInterest_110" xlink:type="arc" order="47" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_110" xlink:to="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_110" xlink:type="arc" order="48" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity_110" xlink:type="arc" order="49" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/BalanceSheetsUnauditedParenthetical" xlink:title="00000003 - Statement - Condensed Consolidated Balance Sheets Unaudited (Parenthetical)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonrelatedPartyMember" xlink:label="loc_us-gaapNonrelatedPartyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapNonrelatedPartyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember" xlink:label="loc_us-gaapVariableInterestEntityPrimaryBeneficiaryMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_us-gaapVariableInterestEntityPrimaryBeneficiaryMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember_60" xlink:type="arc" order="61" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaapCommonClassBMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassBMember_80" xlink:type="arc" order="81" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaapAllowanceForDoubtfulAccountsReceivableCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAllowanceForDoubtfulAccountsReceivableCurrent_110" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulOtherReceivablesCurrent" xlink:label="loc_us-gaapAllowanceForDoubtfulOtherReceivablesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAllowanceForDoubtfulOtherReceivablesCurrent_110" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsPayableCurrent_110" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AccruedLiabilitiesAndOtherLiabilitiesCurrent" xlink:label="loc_VIOTAccruedLiabilitiesAndOtherLiabilitiesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_VIOTAccruedLiabilitiesAndOtherLiabilitiesCurrent_110" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare_110" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaapCommonStockSharesAuthorized_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesAuthorized_110" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued_110" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesOutstanding_110" xlink:type="arc" order="7" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/StatementsOfComprehensiveIncomeLossUnaudited" xlink:title="00000004 - Statement - Condensed Consolidated Statements of Comprehensive Income (Loss) Unaudited">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="loc_us-gaapScheduleOfDefinedBenefitPlansDisclosuresTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonrelatedPartyMember" xlink:label="loc_us-gaapNonrelatedPartyMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapNonrelatedPartyMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenuesAbstract" xlink:label="loc_us-gaapRevenuesAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapRevenuesAbstract_70" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRevenuesAbstract_70" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_70" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaapCostOfRevenue_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRevenuesAbstract_70" xlink:to="loc_us-gaapCostOfRevenue_70" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaapGrossProfit_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRevenuesAbstract_70" xlink:to="loc_us-gaapGrossProfit_70" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaapOperatingExpensesAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRevenuesAbstract_70" xlink:to="loc_us-gaapOperatingExpensesAbstract_70" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaapResearchAndDevelopmentExpense_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapResearchAndDevelopmentExpense_70" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaapSellingAndMarketingExpense_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapSellingAndMarketingExpense_70" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaapGeneralAndAdministrativeExpense_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapGeneralAndAdministrativeExpense_70" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapOperatingExpenses_70" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherOperatingIncomeExpenseNet" xlink:label="loc_us-gaapOtherOperatingIncomeExpenseNet_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapOtherOperatingIncomeExpenseNet_70" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaapOperatingIncomeLoss_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapOperatingIncomeLoss_70" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_InterestIncomeExpenseAndShortTermInvestmentsIncomeNonoperatingNet" xlink:label="loc_VIOTInterestIncomeExpenseAndShortTermInvestmentsIncomeNonoperatingNet_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_VIOTInterestIncomeExpenseAndShortTermInvestmentsIncomeNonoperatingNet_70" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_70" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaapIncomeTaxExpenseBenefit_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapIncomeTaxExpenseBenefit_70" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_70" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_70" xlink:type="arc" order="14" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaapProfitLoss_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapProfitLoss_70" xlink:type="arc" order="16" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapNetIncomeLossAttributableToNoncontrollingInterest_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapNetIncomeLossAttributableToNoncontrollingInterest_70" xlink:type="arc" order="17" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="loc_us-gaapNetIncomeLossAvailableToCommonStockholdersBasic_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapNetIncomeLossAvailableToCommonStockholdersBasic_70" xlink:type="arc" order="18" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_70" xlink:type="arc" order="19" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_70" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_70" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaapComprehensiveIncomeNetOfTax_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_70" xlink:to="loc_us-gaapComprehensiveIncomeNetOfTax_70" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaapEarningsPerShareAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapEarningsPerShareAbstract_70" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaapEarningsPerShareBasic_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapEarningsPerShareBasic_70" xlink:type="arc" order="23" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaapEarningsPerShareDiluted_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapEarningsPerShareDiluted_70" xlink:type="arc" order="24" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:label="loc_us-gaapWeightedAverageNumberOfSharesOutstandingAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapWeightedAverageNumberOfSharesOutstandingAbstract_70" xlink:type="arc" order="25" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaapWeightedAverageNumberOfSharesOutstandingBasic_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapWeightedAverageNumberOfSharesOutstandingBasic_70" xlink:type="arc" order="26" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaapWeightedAverageNumberOfDilutedSharesOutstanding_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapWeightedAverageNumberOfDilutedSharesOutstanding_70" xlink:type="arc" order="27" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/StatementsOfChangesInShareholdersEquityUnaudited" xlink:title="00000005 - Statement - Condensed Consolidated Statements of Changes in Shareholders&apos; Equity Unaudited">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaapStatementEquityComponentsAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementEquityComponentsAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaapCommonStockMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapCommonStockMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaapAdditionalPaidInCapitalMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAdditionalPaidInCapitalMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember" xlink:label="loc_us-gaapTreasuryStockCommonMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapTreasuryStockCommonMember_30" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaapRetainedEarningsMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapRetainedEarningsMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember_50" xlink:type="arc" order="51" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ParentMember" xlink:label="loc_us-gaapParentMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapParentMember_60" xlink:type="arc" order="61" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaapNoncontrollingInterestMember_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapNoncontrollingInterestMember_70" xlink:type="arc" order="71" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaapCommonClassBMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassBMember_10" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_100" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaapSharesOutstanding_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesOutstanding_100" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonShares" xlink:label="loc_us-gaapTreasuryStockCommonShares_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapTreasuryStockCommonShares_100" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaapProfitLoss_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProfitLoss_100" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_PurchaseOfEquityInterestsFromNoncontrollingInterests" xlink:label="loc_VIOTPurchaseOfEquityInterestsFromNoncontrollingInterests_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_VIOTPurchaseOfEquityInterestsFromNoncontrollingInterests_100" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition" xlink:label="loc_us-gaapAdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_100" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueStockOptionsExercised_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueStockOptionsExercised_100" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesStockOptionsExercised_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesStockOptionsExercised_100" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_100" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodValue" xlink:label="loc_us-gaapStockRepurchasedDuringPeriodValue_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockRepurchasedDuringPeriodValue_100" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodShares" xlink:label="loc_us-gaapStockRepurchasedDuringPeriodShares_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockRepurchasedDuringPeriodShares_100" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_StockIssuedDuringThePeriodAppropriationToStatutoryReserves" xlink:label="loc_VIOTStockIssuedDuringThePeriodAppropriationToStatutoryReserves_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_VIOTStockIssuedDuringThePeriodAppropriationToStatutoryReserves_100" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends" xlink:label="loc_us-gaapDividends_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDividends_100" xlink:type="arc" order="14" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueConversionOfConvertibleSecurities_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueConversionOfConvertibleSecurities_100" xlink:type="arc" order="15" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_100" xlink:type="arc" order="16" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/StatementsOfCashFlowsUnaudited" xlink:title="00000006 - Statement - Condensed Consolidated Statements of Cash Flows Unaudited" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/OrganizationAndPrincipalActivities" xlink:title="999007 - Disclosure - ORGANIZATION AND PRINCIPAL ACTIVITIES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SignificantAccountingPolicies" xlink:title="999008 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ConcentrationAndRisks" xlink:title="999009 - Disclosure - CONCENTRATION AND RISKS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/CashAndCashEquivalents" xlink:title="999010 - Disclosure - CASH AND CASH EQUIVALENTS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RestrictedCash" xlink:title="999011 - Disclosure - RESTRICTED CASH" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Short-termInvestments" xlink:title="999012 - Disclosure - SHORT-TERM INVESTMENTS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/InventoriesNet" xlink:title="999013 - Disclosure - INVENTORIES, NET" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/PrepaidExpensesAndOtherAssets" xlink:title="999014 - Disclosure - PREPAID EXPENSES AND OTHER ASSETS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/PropertyPlantAndEquipmentNet" xlink:title="999015 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT, NET" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/LandUseRightNet" xlink:title="999016 - Disclosure - LAND USE RIGHT, NET" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Borrowings" xlink:title="999017 - Disclosure - BORROWINGS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/AccruedExpensesAndOtherLiabilities" xlink:title="999018 - Disclosure - ACCRUED EXPENSES AND OTHER LIABILITIES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SegmentReporting" xlink:title="999019 - Disclosure - SEGMENT REPORTING" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Revenue" xlink:title="999020 - Disclosure - REVENUE" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/IncomeTaxExpenses" xlink:title="999021 - Disclosure - INCOME TAX EXPENSES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/OrdinaryShares" xlink:title="999022 - Disclosure - ORDINARY SHARES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Share-basedCompensation" xlink:title="999023 - Disclosure - SHARE-BASED COMPENSATION" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/NetIncomeLossPerShare" xlink:title="999024 - Disclosure - NET INCOME (LOSS) PER SHARE" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RelatedPartyTransactions" xlink:title="999025 - Disclosure - RELATED PARTY TRANSACTIONS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/FairValueMeasurements" xlink:title="999026 - Disclosure - FAIR VALUE MEASUREMENTS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Leases" xlink:title="999027 - Disclosure - LEASES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/CommitmentsAndContingencies" xlink:title="999028 - Disclosure - COMMITMENTS AND CONTINGENCIES" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RestrictedNetAssets" xlink:title="999029 - Disclosure - RESTRICTED NET ASSETS" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SubsequentEvent" xlink:title="999030 - Disclosure - SUBSEQUENT EVENT" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/UnauditedCondensedFinancialInformationOfParentCompany" xlink:title="999031 - Disclosure - UNAUDITED CONDENSED FINANCIAL INFORMATION OF THE PARENT COMPANY" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SignificantAccountingPoliciesPolicies" xlink:title="999032 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Policies)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/OrganizationAndPrincipalActivitiesTables" xlink:title="999033 - Disclosure - ORGANIZATION AND PRINCIPAL ACTIVITIES (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SignificantAccountingPoliciesTables" xlink:title="999034 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ConcentrationAndRisksTables" xlink:title="999035 - Disclosure - CONCENTRATION AND RISKS (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/CashAndCashEquivalentsTables" xlink:title="999036 - Disclosure - CASH AND CASH EQUIVALENTS (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/InventoriesNetTables" xlink:title="999037 - Disclosure - INVENTORIES, NET (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/PrepaidExpensesAndOtherAssetsTables" xlink:title="999038 - Disclosure - PREPAID EXPENSES AND OTHER ASSETS (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/PropertyPlantAndEquipmentNetTables" xlink:title="999039 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT, NET (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/LandUseRightNetTables" xlink:title="999040 - Disclosure - LAND USE RIGHT, NET (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/BorrowingsTables" xlink:title="999041 - Disclosure - BORROWINGS (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/AccruedExpensesAndOtherLiabilitiesTables" xlink:title="999042 - Disclosure - ACCRUED EXPENSES AND OTHER LIABILITIES (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RevenueTables" xlink:title="999043 - Disclosure - REVENUE (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/IncomeTaxExpensesTables" xlink:title="999044 - Disclosure - INCOME TAX EXPENSES (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Share-basedCompensationTables" xlink:title="999045 - Disclosure - SHARE-BASED COMPENSATION (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/NetIncomeLossPerShareTables" xlink:title="999046 - Disclosure - NET INCOME (LOSS) PER SHARE (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RelatedPartyTransactionsTables" xlink:title="999047 - Disclosure - RELATED PARTY TRANSACTIONS (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/FairValueMeasurementsTables" xlink:title="999048 - Disclosure - FAIR VALUE MEASUREMENTS (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/LeasesTables" xlink:title="999049 - Disclosure - LEASES (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/CommitmentsAndContingenciesTables" xlink:title="999050 - Disclosure - COMMITMENTS AND CONTINGENCIES (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/UnauditedCondensedFinancialInformationOfParentCompanyTables" xlink:title="999051 - Disclosure - UNAUDITED CONDENSED FINANCIAL INFORMATION OF THE PARENT COMPANY (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfPrincipalSubsidiariesAndViesDetails" xlink:title="999052 - Disclosure - SCHEDULE OF PRINCIPAL SUBSIDIARIES AND VIES (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:label="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:label="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SubsidiariesMember" xlink:label="loc_srtSubsidiariesMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtSubsidiariesMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember" xlink:label="loc_us-gaapVariableInterestEntityPrimaryBeneficiaryMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_us-gaapVariableInterestEntityPrimaryBeneficiaryMember_60" xlink:type="arc" order="61" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis" xlink:label="loc_srtOwnershipAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:to="loc_srtOwnershipAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain" xlink:label="loc_srtOwnershipDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtOwnershipAxis" xlink:to="loc_srtOwnershipDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain" xlink:label="loc_srtOwnershipDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtOwnershipAxis" xlink:to="loc_srtOwnershipDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ViomiHKTechnologyCompanyLimitedMember" xlink:label="loc_VIOTViomiHKTechnologyCompanyLimitedMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTViomiHKTechnologyCompanyLimitedMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_LequanMember" xlink:label="loc_VIOTLequanMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTLequanMember_10" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_CodreamHKMember" xlink:label="loc_VIOTCodreamHKMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTCodreamHKMember_20" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_YunmiHulianMember" xlink:label="loc_VIOTYunmiHulianMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTYunmiHulianMember_30" xlink:type="arc" order="32" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ZhumengHulianMember" xlink:label="loc_VIOTZhumengHulianMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTZhumengHulianMember_40" xlink:type="arc" order="42" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_GuangdongLiziMember" xlink:label="loc_VIOTGuangdongLiziMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTGuangdongLiziMember_50" xlink:type="arc" order="52" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_GuangzhouInterconnectMember" xlink:label="loc_VIOTGuangzhouInterconnectMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTGuangzhouInterconnectMember_60" xlink:type="arc" order="62" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_BeijingViomiMember" xlink:label="loc_VIOTBeijingViomiMember_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtOwnershipDomain" xlink:to="loc_VIOTBeijingViomiMember_70" xlink:type="arc" order="72" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByParent" xlink:label="loc_us-gaapMinorityInterestOwnershipPercentageByParent_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapMinorityInterestOwnershipPercentageByParent_90" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfFinancialStatementAmountsAndBalancesOfViesDetails" xlink:title="999053 - Disclosure - SCHEDULE OF FINANCIAL STATEMENT AMOUNTS AND BALANCES OF VIES (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:label="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:label="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember" xlink:label="loc_us-gaapVariableInterestEntityPrimaryBeneficiaryMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_us-gaapVariableInterestEntityPrimaryBeneficiaryMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_20" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srtCounterpartyNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:to="loc_srtCounterpartyNameAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_GroupCompaniesMember" xlink:label="loc_VIOTGroupCompaniesMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTGroupCompaniesMember_40" xlink:type="arc" order="42" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_RelatedPartyAndThirdPartyMember" xlink:label="loc_VIOTRelatedPartyAndThirdPartyMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTRelatedPartyAndThirdPartyMember_60" xlink:type="arc" order="62" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_110" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapAccountsReceivableNetCurrent_110" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="loc_us-gaapReceivablesNetCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapReceivablesNetCurrent_110" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AmountDueFromGroupCompaniesNonCurrent" xlink:label="loc_VIOTAmountDueFromGroupCompaniesNonCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_VIOTAmountDueFromGroupCompaniesNonCurrent_110" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapInventoryNet_110" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaapOtherAssetsNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapOtherAssetsNoncurrent_110" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapAssets_110" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapAccountsPayableCurrent_110" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AmountDueToGroupCompaniesNonCurrent" xlink:label="loc_VIOTAmountDueToGroupCompaniesNonCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_VIOTAmountDueToGroupCompaniesNonCurrent_110" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaapAccruedLiabilitiesCurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapAccruedLiabilitiesCurrent_110" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaapOtherLiabilitiesNoncurrent_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapOtherLiabilitiesNoncurrent_110" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapLiabilities_110" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_110" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaapCostOfRevenue_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapCostOfRevenue_110" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapNetIncomeLoss_110" xlink:type="arc" order="14" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfFinancialStatementAmountsAndBalancesOfViesDetailsParenthetical" xlink:title="999054 - Disclosure - SCHEDULE OF FINANCIAL STATEMENT AMOUNTS AND BALANCES OF VIES (Details) (Parenthetical)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:label="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:label="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_VariableInterestEntityToVariableInterestEntityPrimaryBeneficiaryAndSubsidiariesMember" xlink:label="loc_VIOTVariableInterestEntityToVariableInterestEntityPrimaryBeneficiaryAndSubsidiariesMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_VIOTVariableInterestEntityToVariableInterestEntityPrimaryBeneficiaryAndSubsidiariesMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaapAllowanceForDoubtfulAccountsReceivableCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapAllowanceForDoubtfulAccountsReceivableCurrent_50" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_50" xlink:type="arc" order="1" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/OrganizationAndPrincipalActivitiesDetailsNarrative" xlink:title="999055 - Disclosure - ORGANIZATION AND PRINCIPAL ACTIVITIES (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfActivityInAllowanceForCreditLossesRelatedToAccountsAndNotesReceivableAndOtherReceivablesFromRelatedPartiesDetails" xlink:title="999056 - Disclosure - SCHEDULE OF ACTIVITY IN ALLOWANCE FOR CREDIT LOSSES RELATED TO ACCOUNTS AND NOTES RECEIVABLE AND OTHER RECEIVABLES FROM RELATED PARTIES (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SignificantAccountingPoliciesDetailsNarrative" xlink:title="999057 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductInformationLineItems" xlink:label="loc_us-gaapProductInformationLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfProductInformationTable" xlink:label="loc_us-gaapScheduleOfProductInformationTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapScheduleOfProductInformationTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srtProductOrServiceAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_srtProductOrServiceAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srtProductsAndServicesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtProductOrServiceAxis" xlink:to="loc_srtProductsAndServicesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srtProductsAndServicesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtProductOrServiceAxis" xlink:to="loc_srtProductsAndServicesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_InstallationServicesMember" xlink:label="loc_VIOTInstallationServicesMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTInstallationServicesMember_50" xlink:type="arc" order="51" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_MembershipServiceMember" xlink:label="loc_VIOTMembershipServiceMember_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTMembershipServiceMember_70" xlink:type="arc" order="71" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis" xlink:label="loc_us-gaapStatementOfIncomeLocationBalanceAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_us-gaapStatementOfIncomeLocationBalanceAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyExchangeRateTranslation1" xlink:label="loc_us-gaapForeignCurrencyExchangeRateTranslation1_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapForeignCurrencyExchangeRateTranslation1_120" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_NumberOfInstallmentPaymentsFromCustomer" xlink:label="loc_VIOTNumberOfInstallmentPaymentsFromCustomer_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTNumberOfInstallmentPaymentsFromCustomer_120" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_PercentageOfSecondInstallmentPaymentArrangementToRevenue" xlink:label="loc_VIOTPercentageOfSecondInstallmentPaymentArrangementToRevenue_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTPercentageOfSecondInstallmentPaymentArrangementToRevenue_120" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ContractWithCustomerExpectedSalesReturn" xlink:label="loc_VIOTContractWithCustomerExpectedSalesReturn_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTContractWithCustomerExpectedSalesReturn_120" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerRightToRecoverProduct" xlink:label="loc_us-gaapContractWithCustomerRightToRecoverProduct_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerRightToRecoverProduct_120" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerRefundLiability" xlink:label="loc_us-gaapContractWithCustomerRefundLiability_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerRefundLiability_120" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ValueAddedTaxRate" xlink:label="loc_VIOTValueAddedTaxRate_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTValueAddedTaxRate_120" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiability" xlink:label="loc_us-gaapContractWithCustomerLiability_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerLiability_120" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized" xlink:label="loc_us-gaapContractWithCustomerLiabilityRevenueRecognized_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerLiabilityRevenueRecognized_120" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligation" xlink:label="loc_us-gaapRevenueRemainingPerformanceObligation_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapRevenueRemainingPerformanceObligation_120" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ProvisionForAccountsReceivableLoanLeaseAndOtherLosses" xlink:label="loc_VIOTProvisionForAccountsReceivableLoanLeaseAndOtherLosses_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTProvisionForAccountsReceivableLoanLeaseAndOtherLosses_120" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:label="loc_us-gaapFinancingReceivableAllowanceForCreditLosses_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapFinancingReceivableAllowanceForCreditLosses_120" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:label="loc_us-gaapUnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapUnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_120" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_StatutoryReserveFunds" xlink:label="loc_VIOTStatutoryReserveFunds_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTStatutoryReserveFunds_120" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AccumulatedStatutoryReserveFunds" xlink:label="loc_VIOTAccumulatedStatutoryReserveFunds_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTAccumulatedStatutoryReserveFunds_120" xlink:type="arc" order="14" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SignificantAccountingPoliciesDetailsNarrativeDefOnly" xlink:title="999057 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductInformationLineItems" xlink:label="loc_us-gaapProductInformationLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfProductInformationTable" xlink:label="loc_us-gaapScheduleOfProductInformationTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapScheduleOfProductInformationTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srtProductOrServiceAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_srtProductOrServiceAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srtProductsAndServicesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtProductOrServiceAxis" xlink:to="loc_srtProductsAndServicesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srtProductsAndServicesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtProductOrServiceAxis" xlink:to="loc_srtProductsAndServicesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_InstallationServicesMember" xlink:label="loc_VIOTInstallationServicesMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTInstallationServicesMember_50" xlink:type="arc" order="51" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_MembershipServiceMember" xlink:label="loc_VIOTMembershipServiceMember_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTMembershipServiceMember_70" xlink:type="arc" order="71" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyExchangeRateTranslation1" xlink:label="loc_us-gaapForeignCurrencyExchangeRateTranslation1_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapForeignCurrencyExchangeRateTranslation1_120" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_NumberOfInstallmentPaymentsFromCustomer" xlink:label="loc_VIOTNumberOfInstallmentPaymentsFromCustomer_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTNumberOfInstallmentPaymentsFromCustomer_120" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_PercentageOfSecondInstallmentPaymentArrangementToRevenue" xlink:label="loc_VIOTPercentageOfSecondInstallmentPaymentArrangementToRevenue_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTPercentageOfSecondInstallmentPaymentArrangementToRevenue_120" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ContractWithCustomerExpectedSalesReturn" xlink:label="loc_VIOTContractWithCustomerExpectedSalesReturn_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTContractWithCustomerExpectedSalesReturn_120" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerRightToRecoverProduct" xlink:label="loc_us-gaapContractWithCustomerRightToRecoverProduct_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerRightToRecoverProduct_120" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerRefundLiability" xlink:label="loc_us-gaapContractWithCustomerRefundLiability_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerRefundLiability_120" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ValueAddedTaxRate" xlink:label="loc_VIOTValueAddedTaxRate_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTValueAddedTaxRate_120" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiability" xlink:label="loc_us-gaapContractWithCustomerLiability_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerLiability_120" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized" xlink:label="loc_us-gaapContractWithCustomerLiabilityRevenueRecognized_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapContractWithCustomerLiabilityRevenueRecognized_120" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligation" xlink:label="loc_us-gaapRevenueRemainingPerformanceObligation_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapRevenueRemainingPerformanceObligation_120" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ProvisionForAccountsReceivableLoanLeaseAndOtherLosses" xlink:label="loc_VIOTProvisionForAccountsReceivableLoanLeaseAndOtherLosses_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTProvisionForAccountsReceivableLoanLeaseAndOtherLosses_120" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:label="loc_us-gaapFinancingReceivableAllowanceForCreditLosses_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapFinancingReceivableAllowanceForCreditLosses_120" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:label="loc_us-gaapUnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapUnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_120" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_StatutoryReserveFunds" xlink:label="loc_VIOTStatutoryReserveFunds_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTStatutoryReserveFunds_120" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AccumulatedStatutoryReserveFunds" xlink:label="loc_VIOTAccumulatedStatutoryReserveFunds_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_VIOTAccumulatedStatutoryReserveFunds_120" xlink:type="arc" order="14" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfConcentrationOfRiskDetails" xlink:title="999058 - Disclosure - SUMMARY OF CONCENTRATION OF RISK (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="loc_us-gaapConcentrationRiskLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTable" xlink:label="loc_us-gaapConcentrationRiskTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConcentrationRiskLineItems" xlink:to="loc_us-gaapConcentrationRiskTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MajorCustomersAxis" xlink:label="loc_srtMajorCustomersAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConcentrationRiskTable" xlink:to="loc_srtMajorCustomersAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtMajorCustomersAxis" xlink:to="loc_srtNameOfMajorCustomerDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtMajorCustomersAxis" xlink:to="loc_srtNameOfMajorCustomerDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_CompanyAMember" xlink:label="loc_VIOTCompanyAMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_VIOTCompanyAMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_CompanyBMember" xlink:label="loc_VIOTCompanyBMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_VIOTCompanyBMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaapConcentrationRiskByBenchmarkAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConcentrationRiskTable" xlink:to="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AccountsAndNotesReceivableMember" xlink:label="loc_VIOTAccountsAndNotesReceivableMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_VIOTAccountsAndNotesReceivableMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableMember" xlink:label="loc_us-gaapAccountsReceivableMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_us-gaapAccountsReceivableMember_80" xlink:type="arc" order="82" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_OtherReceivablesMember" xlink:label="loc_VIOTOtherReceivablesMember_160" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_VIOTOtherReceivablesMember_160" xlink:type="arc" order="162" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SalesRevenueNetMember" xlink:label="loc_us-gaapSalesRevenueNetMember_200" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_us-gaapSalesRevenueNetMember_200" xlink:type="arc" order="202" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaapConcentrationRiskByTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConcentrationRiskTable" xlink:to="loc_us-gaapConcentrationRiskByTypeAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaapConcentrationRiskTypeDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByTypeAxis" xlink:to="loc_us-gaapConcentrationRiskTypeDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaapConcentrationRiskTypeDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConcentrationRiskByTypeAxis" xlink:to="loc_us-gaapConcentrationRiskTypeDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditConcentrationRiskMember" xlink:label="loc_us-gaapCreditConcentrationRiskMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_us-gaapCreditConcentrationRiskMember_0" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromRightsConcentrationRiskMember" xlink:label="loc_us-gaapRevenueFromRightsConcentrationRiskMember_200" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_us-gaapRevenueFromRightsConcentrationRiskMember_200" xlink:type="arc" order="203" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srtCounterpartyNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConcentrationRiskTable" xlink:to="loc_srtCounterpartyNameAxis" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_XiaomiMember" xlink:label="loc_VIOTXiaomiMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTXiaomiMember_80" xlink:type="arc" order="81" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_FoshanViomiMember" xlink:label="loc_VIOTFoshanViomiMember_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTFoshanViomiMember_120" xlink:type="arc" order="121" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapConcentrationRiskTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_80" xlink:type="arc" order="84" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsAndNotesReceivableNet" xlink:label="loc_us-gaapAccountsAndNotesReceivableNet_230" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskLineItems" xlink:to="loc_us-gaapAccountsAndNotesReceivableNet_230" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="loc_us-gaapConcentrationRiskPercentage1_230" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskLineItems" xlink:to="loc_us-gaapConcentrationRiskPercentage1_230" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNet" xlink:label="loc_us-gaapAccountsReceivableNet_230" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskLineItems" xlink:to="loc_us-gaapAccountsReceivableNet_230" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivables" xlink:label="loc_us-gaapOtherReceivables_230" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskLineItems" xlink:to="loc_us-gaapOtherReceivables_230" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_230" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_230" xlink:type="arc" order="4" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfCashAndCashEquivalentsDetails" xlink:title="999059 - Disclosure - SUMMARY OF CASH AND CASH EQUIVALENTS (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaapAwardTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="loc_us-gaapAwardTypeAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardTypeAxis" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapAwardTypeAxis" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_RMBMember" xlink:label="loc_VIOTRMBMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_VIOTRMBMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_USDollarMember" xlink:label="loc_VIOTUSDollarMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_VIOTUSDollarMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_OthersMember" xlink:label="loc_VIOTOthersMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_VIOTOthersMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_90" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RestrictedCashDetailsNarrative" xlink:title="999060 - Disclosure - RESTRICTED CASH (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Short-termInvestmentsDetailsNarrative" xlink:title="999061 - Disclosure - SHORT-TERM INVESTMENTS (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfInventoriesDetails" xlink:title="999062 - Disclosure - SCHEDULE OF INVENTORIES (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/InventoriesNetDetailsNarrative" xlink:title="999063 - Disclosure - INVENTORIES, NET (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfPrepaidExpensesAndOtherAssetsDetails" xlink:title="999064 - Disclosure - SCHEDULE OF PREPAID EXPENSES AND OTHER ASSETS (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfPropertyPlantAndEquipmentNetDetails" xlink:title="999065 - Disclosure - SCHEDULE OF PROPERTY, PLANT, AND EQUIPMENT, NET (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaapPropertyPlantAndEquipmentLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaapScheduleOfPropertyPlantAndEquipmentTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapPropertyPlantAndEquipmentLineItems" xlink:to="loc_us-gaapScheduleOfPropertyPlantAndEquipmentTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfPropertyPlantAndEquipmentTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BuildingMember" xlink:label="loc_us-gaapBuildingMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapBuildingMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComputerEquipmentMember" xlink:label="loc_us-gaapComputerEquipmentMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapComputerEquipmentMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VehiclesMember" xlink:label="loc_us-gaapVehiclesMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapVehiclesMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaapPropertyPlantAndEquipmentGross_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentGross_90" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentLineItems" xlink:to="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_90" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet_90" xlink:type="arc" order="2" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/PropertyPlantAndEquipmentNetDetailsNarrative" xlink:title="999066 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT, NET (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfLandUseRightNetDetails" xlink:title="999067 - Disclosure - SUMMARY OF LAND USE RIGHT, NET (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfEstimatedFutureAmortizationExpenseForLandUseRightsDetails" xlink:title="999068 - Disclosure - SCHEDULE OF ESTIMATED FUTURE AMORTIZATION EXPENSE FOR LAND USE RIGHTS (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/LandUseRightNetDetailsNarrative" xlink:title="999069 - Disclosure - LAND USE RIGHT, NET (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfShort-termBorrowingsDetails" xlink:title="999070 - Disclosure - SCHEDULE OF SHORT-TERM BORROWINGS (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermDebtLineItems" xlink:label="loc_us-gaapShortTermDebtLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShortTermDebtTable" xlink:label="loc_us-gaapScheduleOfShortTermDebtTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapScheduleOfShortTermDebtTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaapDebtInstrumentAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShortTermDebtTable" xlink:to="loc_us-gaapDebtInstrumentAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaapDebtInstrumentNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapDebtInstrumentAxis" xlink:to="loc_us-gaapDebtInstrumentNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaapDebtInstrumentNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapDebtInstrumentAxis" xlink:to="loc_us-gaapDebtInstrumentNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AgriculturalBankOfChinaMember" xlink:label="loc_VIOTAgriculturalBankOfChinaMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDebtInstrumentNameDomain" xlink:to="loc_VIOTAgriculturalBankOfChinaMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_BankOfChinaMember" xlink:label="loc_VIOTBankOfChinaMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDebtInstrumentNameDomain" xlink:to="loc_VIOTBankOfChinaMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_IndustrialAndCommercialBankOfChinaMember" xlink:label="loc_VIOTIndustrialAndCommercialBankOfChinaMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDebtInstrumentNameDomain" xlink:to="loc_VIOTIndustrialAndCommercialBankOfChinaMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermBorrowings" xlink:label="loc_us-gaapShortTermBorrowings_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapShortTermBorrowings_90" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfShort-termBorrowingsDetailsParenthetical" xlink:title="999071 - Disclosure - SCHEDULE OF SHORT-TERM BORROWINGS (Details) (Parenthetical)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermDebtLineItems" xlink:label="loc_us-gaapShortTermDebtLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShortTermDebtTable" xlink:label="loc_us-gaapScheduleOfShortTermDebtTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapScheduleOfShortTermDebtTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaapDebtInstrumentAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShortTermDebtTable" xlink:to="loc_us-gaapDebtInstrumentAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaapDebtInstrumentNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapDebtInstrumentAxis" xlink:to="loc_us-gaapDebtInstrumentNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaapDebtInstrumentNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapDebtInstrumentAxis" xlink:to="loc_us-gaapDebtInstrumentNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_BankOfChinaMember" xlink:label="loc_VIOTBankOfChinaMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDebtInstrumentNameDomain" xlink:to="loc_VIOTBankOfChinaMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_IndustrialAndCommercialBankOfChinaMember" xlink:label="loc_VIOTIndustrialAndCommercialBankOfChinaMember_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDebtInstrumentNameDomain" xlink:to="loc_VIOTIndustrialAndCommercialBankOfChinaMember_120" xlink:type="arc" order="121" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermBorrowings" xlink:label="loc_us-gaapShortTermBorrowings_160" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapShortTermBorrowings_160" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermDebtTerms" xlink:label="loc_us-gaapShortTermDebtTerms_160" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapShortTermDebtTerms_160" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentMaturityDate" xlink:label="loc_us-gaapDebtInstrumentMaturityDate_160" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapDebtInstrumentMaturityDate_160" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermDebtPercentageBearingFixedInterestRate" xlink:label="loc_us-gaapShortTermDebtPercentageBearingFixedInterestRate_160" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtLineItems" xlink:to="loc_us-gaapShortTermDebtPercentageBearingFixedInterestRate_160" xlink:type="arc" order="3" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfLong-termBorrowingsDetails" xlink:title="999072 - Disclosure - SCHEDULE OF LONG-TERM BORROWINGS (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaapLineOfCreditFacilityLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityTable" xlink:label="loc_us-gaapLineOfCreditFacilityTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCreditFacilityTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaapCreditFacilityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapCreditFacilityAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaapCreditFacilityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapCreditFacilityAxis" xlink:to="loc_us-gaapCreditFacilityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaapCreditFacilityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapCreditFacilityAxis" xlink:to="loc_us-gaapCreditFacilityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaapLineOfCreditMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapCreditFacilityDomain" xlink:to="loc_us-gaapLineOfCreditMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaapLongTermDebt_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLongTermDebt_50" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_LongTermDebtCurrentPortion" xlink:label="loc_VIOTLongTermDebtCurrentPortion_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_VIOTLongTermDebtCurrentPortion_50" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaapLongTermDebtNoncurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLongTermDebtNoncurrent_50" xlink:type="arc" order="2" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfFutureMaturitiesOfLong-termBorrowingsDetails" xlink:title="999073 - Disclosure - SCHEDULE OF FUTURE MATURITIES OF LONG-TERM BORROWINGS (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/BorrowingsDetailsNarrative" xlink:title="999074 - Disclosure - BORROWINGS (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaapLineOfCreditFacilityLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityTable" xlink:label="loc_us-gaapLineOfCreditFacilityTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCreditFacilityTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaapCreditFacilityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapCreditFacilityAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaapCreditFacilityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapCreditFacilityAxis" xlink:to="loc_us-gaapCreditFacilityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaapCreditFacilityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapCreditFacilityAxis" xlink:to="loc_us-gaapCreditFacilityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaapLineOfCreditMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapCreditFacilityDomain" xlink:to="loc_us-gaapLineOfCreditMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="loc_srtRangeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_srtRangeAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="loc_srtRangeMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtRangeAxis" xlink:to="loc_srtRangeMember" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="loc_srtRangeMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtRangeAxis" xlink:to="loc_srtRangeMember_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="loc_srtMinimumMember_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRangeMember" xlink:to="loc_srtMinimumMember_70" xlink:type="arc" order="71" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="loc_srtMaximumMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRangeMember" xlink:to="loc_srtMaximumMember_80" xlink:type="arc" order="81" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaapFinancialInstrumentAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapFinancialInstrumentAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnusedLinesOfCreditMember" xlink:label="loc_us-gaapUnusedLinesOfCreditMember_100" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_us-gaapUnusedLinesOfCreditMember_100" xlink:type="arc" order="102" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusAxis" xlink:label="loc_us-gaapPledgedStatusAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapPledgedStatusAxis" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain" xlink:label="loc_us-gaapPledgedStatusDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPledgedStatusAxis" xlink:to="loc_us-gaapPledgedStatusDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain" xlink:label="loc_us-gaapPledgedStatusDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapPledgedStatusAxis" xlink:to="loc_us-gaapPledgedStatusDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetPledgedAsCollateralMember" xlink:label="loc_us-gaapAssetPledgedAsCollateralMember_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPledgedStatusDomain" xlink:to="loc_us-gaapAssetPledgedAsCollateralMember_110" xlink:type="arc" order="111" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgingPurposeAxis" xlink:label="loc_us-gaapPledgingPurposeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapPledgingPurposeAxis" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgingPurposeDomain" xlink:label="loc_us-gaapPledgingPurposeDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPledgingPurposeAxis" xlink:to="loc_us-gaapPledgingPurposeDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgingPurposeDomain" xlink:label="loc_us-gaapPledgingPurposeDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapPledgingPurposeAxis" xlink:to="loc_us-gaapPledgingPurposeDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaapLineOfCreditMember_110" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPledgingPurposeDomain" xlink:to="loc_us-gaapLineOfCreditMember_110" xlink:type="arc" order="112" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseShortTermBorrowings" xlink:label="loc_us-gaapInterestExpenseShortTermBorrowings_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapInterestExpenseShortTermBorrowings_130" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermDebtWeightedAverageInterestRate" xlink:label="loc_us-gaapShortTermDebtWeightedAverageInterestRate_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapShortTermDebtWeightedAverageInterestRate_130" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:label="loc_us-gaapProceedsFromLongTermLinesOfCredit_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapProceedsFromLongTermLinesOfCredit_130" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLinesOfCredit" xlink:label="loc_us-gaapRepaymentsOfLinesOfCredit_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapRepaymentsOfLinesOfCredit_130" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod" xlink:label="loc_us-gaapLineOfCreditFacilityInterestRateDuringPeriod_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCreditFacilityInterestRateDuringPeriod_130" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit" xlink:label="loc_us-gaapRepaymentsOfLongTermLinesOfCredit_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapRepaymentsOfLongTermLinesOfCredit_130" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaapLineOfCredit_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCredit_130" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="loc_us-gaapLineOfCreditFacilityRemainingBorrowingCapacity_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCreditFacilityRemainingBorrowingCapacity_130" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentOtherNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentOtherNet_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentOtherNet_130" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_LandUseRightsNet" xlink:label="loc_VIOTLandUseRightsNet_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_VIOTLandUseRightsNet_130" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseBorrowings" xlink:label="loc_us-gaapInterestExpenseBorrowings_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapInterestExpenseBorrowings_130" xlink:type="arc" order="10" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfAccruedExpensesAndOtherLiabilitiesDetails" xlink:title="999075 - Disclosure - SCHEDULE OF ACCRUED EXPENSES AND OTHER LIABILITIES (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfProductWarrantActivitiesDetails" xlink:title="999076 - Disclosure - SCHEDULE OF PRODUCT WARRANT ACTIVITIES (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SegmentReportingDetailsNarrative" xlink:title="999077 - Disclosure - SEGMENT REPORTING (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfRevenueDetails" xlink:title="999078 - Disclosure - SCHEDULE OF REVENUE (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="loc_us-gaapDisaggregationOfRevenueLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:label="loc_us-gaapDisaggregationOfRevenueTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapDisaggregationOfRevenueLineItems" xlink:to="loc_us-gaapDisaggregationOfRevenueTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srtProductOrServiceAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapDisaggregationOfRevenueTable" xlink:to="loc_srtProductOrServiceAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srtProductsAndServicesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtProductOrServiceAxis" xlink:to="loc_srtProductsAndServicesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srtProductsAndServicesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtProductOrServiceAxis" xlink:to="loc_srtProductsAndServicesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_SaleOfHomeWaterSolutionsMember" xlink:label="loc_VIOTSaleOfHomeWaterSolutionsMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTSaleOfHomeWaterSolutionsMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_SaleOfConsumablesMember" xlink:label="loc_VIOTSaleOfConsumablesMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTSaleOfConsumablesMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_SaleofKitchenAppliancesandOthersMember" xlink:label="loc_VIOTSaleofKitchenAppliancesandOthersMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_VIOTSaleofKitchenAppliancesandOthersMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductMember" xlink:label="loc_us-gaapProductMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_us-gaapProductMember_60" xlink:type="arc" order="61" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ServiceMember" xlink:label="loc_us-gaapServiceMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtProductsAndServicesDomain" xlink:to="loc_us-gaapServiceMember_80" xlink:type="arc" order="81" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDisaggregationOfRevenueLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_130" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfCurrentAndDeferredComponentsDetails" xlink:title="999079 - Disclosure - SCHEDULE OF CURRENT AND DEFERRED COMPONENTS (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfReconciliationIncomeTaxExpensesDetails" xlink:title="999080 - Disclosure - SCHEDULE OF RECONCILIATION INCOME TAX EXPENSES (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfPerSharesEffectOfTaxDetails" xlink:title="999081 - Disclosure - SCHEDULE OF PER SHARES EFFECT OF TAX (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfDeferredTaxAssetsDetails" xlink:title="999082 - Disclosure - SCHEDULE OF DEFERRED TAX ASSETS (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/ScheduleOfMovementOfValuationAllowanceDetails" xlink:title="999083 - Disclosure - SCHEDULE OF MOVEMENT OF VALUATION ALLOWANCE (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/IncomeTaxExpensesDetailsNarrative" xlink:title="999084 - Disclosure - INCOME TAX EXPENSES (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLossCarryforwardsLineItems" xlink:label="loc_us-gaapOperatingLossCarryforwardsLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLossCarryforwardsTable" xlink:label="loc_us-gaapOperatingLossCarryforwardsTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_us-gaapOperatingLossCarryforwardsTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srtStatementGeographicalAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapOperatingLossCarryforwardsTable" xlink:to="loc_srtStatementGeographicalAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srtSegmentGeographicalDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtStatementGeographicalAxis" xlink:to="loc_srtSegmentGeographicalDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srtSegmentGeographicalDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtStatementGeographicalAxis" xlink:to="loc_srtSegmentGeographicalDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_HK" xlink:label="loc_countryHK_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtSegmentGeographicalDomain" xlink:to="loc_countryHK_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CN" xlink:label="loc_countryCN_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtSegmentGeographicalDomain" xlink:to="loc_countryCN_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityNameAxis" xlink:label="loc_us-gaapIncomeTaxAuthorityNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapOperatingLossCarryforwardsTable" xlink:to="loc_us-gaapIncomeTaxAuthorityNameAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityNameDomain" xlink:label="loc_us-gaapIncomeTaxAuthorityNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapIncomeTaxAuthorityNameAxis" xlink:to="loc_us-gaapIncomeTaxAuthorityNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityNameDomain" xlink:label="loc_us-gaapIncomeTaxAuthorityNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapIncomeTaxAuthorityNameAxis" xlink:to="loc_us-gaapIncomeTaxAuthorityNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_HongKongIncomeTaxWithinTwoMillionMember" xlink:label="loc_VIOTHongKongIncomeTaxWithinTwoMillionMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapIncomeTaxAuthorityNameDomain" xlink:to="loc_VIOTHongKongIncomeTaxWithinTwoMillionMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_HongKongIncomeTaxBeyondTwoMillionMember" xlink:label="loc_VIOTHongKongIncomeTaxBeyondTwoMillionMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapIncomeTaxAuthorityNameDomain" xlink:to="loc_VIOTHongKongIncomeTaxBeyondTwoMillionMember_10" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityAxis" xlink:label="loc_us-gaapIncomeTaxAuthorityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapOperatingLossCarryforwardsTable" xlink:to="loc_us-gaapIncomeTaxAuthorityAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaapIncomeTaxAuthorityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapIncomeTaxAuthorityAxis" xlink:to="loc_us-gaapIncomeTaxAuthorityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaapIncomeTaxAuthorityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapIncomeTaxAuthorityAxis" xlink:to="loc_us-gaapIncomeTaxAuthorityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_EnterpriseIncomeTaxMember" xlink:label="loc_VIOTEnterpriseIncomeTaxMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapIncomeTaxAuthorityDomain" xlink:to="loc_VIOTEnterpriseIncomeTaxMember_40" xlink:type="arc" order="42" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_SubsidiariesAndVariableInterestEntitiesAndPredecessorOperationsMember" xlink:label="loc_VIOTSubsidiariesAndVariableInterestEntitiesAndPredecessorOperationsMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapIncomeTaxAuthorityDomain" xlink:to="loc_VIOTSubsidiariesAndVariableInterestEntitiesAndPredecessorOperationsMember_50" xlink:type="arc" order="52" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="loc_deiLegalEntityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapOperatingLossCarryforwardsTable" xlink:to="loc_deiLegalEntityAxis" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="loc_deiEntityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_deiLegalEntityAxis" xlink:to="loc_deiEntityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="loc_deiEntityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_deiLegalEntityAxis" xlink:to="loc_deiEntityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_NewTechnologyEnterprisesMember" xlink:label="loc_VIOTNewTechnologyEnterprisesMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_VIOTNewTechnologyEnterprisesMember_60" xlink:type="arc" order="62" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodAxis" xlink:label="loc_us-gaapTaxPeriodAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapOperatingLossCarryforwardsTable" xlink:to="loc_us-gaapTaxPeriodAxis" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain" xlink:label="loc_us-gaapTaxPeriodDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapTaxPeriodAxis" xlink:to="loc_us-gaapTaxPeriodDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxPeriodDomain" xlink:label="loc_us-gaapTaxPeriodDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapTaxPeriodAxis" xlink:to="loc_us-gaapTaxPeriodDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LatestTaxYearMember" xlink:label="loc_us-gaapLatestTaxYearMember_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTaxPeriodDomain" xlink:to="loc_us-gaapLatestTaxYearMember_90" xlink:type="arc" order="92" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaapTypeOfArrangementAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapOperatingLossCarryforwardsTable" xlink:to="loc_us-gaapTypeOfArrangementAxis" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_PRCAndHongKongSpecialAdministrativeRegionMember" xlink:label="loc_VIOTPRCAndHongKongSpecialAdministrativeRegionMember_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:to="loc_VIOTPRCAndHongKongSpecialAdministrativeRegionMember_120" xlink:type="arc" order="122" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_ArrangementBetweenPRCAndHongKongSpecialAdministrativeRegionOnAvoidanceOfDoubleTaxationAndPreventionOfFiscalEvasionWithRespectToTaxesOnIncomeAndCapitalMember" xlink:label="loc_VIOTArrangementBetweenPRCAndHongKongSpecialAdministrativeRegionOnAvoidanceOfDoubleTaxationAndPreventionOfFiscalEvasionWithRespectToTaxesOnIncomeAndCapitalMember_130" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:to="loc_VIOTArrangementBetweenPRCAndHongKongSpecialAdministrativeRegionOnAvoidanceOfDoubleTaxationAndPreventionOfFiscalEvasionWithRespectToTaxesOnIncomeAndCapitalMember_130" xlink:type="arc" order="132" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaapEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_us-gaapEffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_180" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyTaxReturnOfCapitalDistribution" xlink:label="loc_us-gaapInvestmentCompanyTaxReturnOfCapitalDistribution_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_us-gaapInvestmentCompanyTaxReturnOfCapitalDistribution_180" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_PercentageOfQualifiedResearchAndDevelopmentExpensesEnterprisesAreEntitledToClaimAsAdditionalTaxDeduction" xlink:label="loc_VIOTPercentageOfQualifiedResearchAndDevelopmentExpensesEnterprisesAreEntitledToClaimAsAdditionalTaxDeduction_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_VIOTPercentageOfQualifiedResearchAndDevelopmentExpensesEnterprisesAreEntitledToClaimAsAdditionalTaxDeduction_180" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_WithholdingIncomeTaxRate" xlink:label="loc_VIOTWithholdingIncomeTaxRate_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_VIOTWithholdingIncomeTaxRate_180" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_MinimumPercentageOfEquityInterestsInPRCForeignInvestedEnterpriseToBeSubjectToSpecialWithholdingTaxRate" xlink:label="loc_VIOTMinimumPercentageOfEquityInterestsInPRCForeignInvestedEnterpriseToBeSubjectToSpecialWithholdingTaxRate_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_VIOTMinimumPercentageOfEquityInterestsInPRCForeignInvestedEnterpriseToBeSubjectToSpecialWithholdingTaxRate_180" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UndistributedEarnings" xlink:label="loc_us-gaapUndistributedEarnings_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_us-gaapUndistributedEarnings_180" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:label="loc_us-gaapUnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_us-gaapUnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense_180" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_StatuteOfLimitations" xlink:label="loc_VIOTStatuteOfLimitations_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_VIOTStatuteOfLimitations_180" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_StatuteOfLimitationsExtendedPeriod" xlink:label="loc_VIOTStatuteOfLimitationsExtendedPeriod_180" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingLossCarryforwardsLineItems" xlink:to="loc_VIOTStatuteOfLimitationsExtendedPeriod_180" xlink:type="arc" order="8" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/OrdinarySharesDetailsNarrative" xlink:title="999085 - Disclosure - ORDINARY SHARES (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaapClassOfStockLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaapScheduleOfStockByClassTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapScheduleOfStockByClassTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfStockByClassTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember_10" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaapCommonClassBMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassBMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredClassAMember" xlink:label="loc_us-gaapPreferredClassAMember_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapPreferredClassAMember_80" xlink:type="arc" order="82" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaapSubsidiarySaleOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfStockByClassTable" xlink:to="loc_us-gaapSubsidiarySaleOfStockAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaapSaleOfStockNameOfTransactionDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapSubsidiarySaleOfStockAxis" xlink:to="loc_us-gaapSaleOfStockNameOfTransactionDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaapSaleOfStockNameOfTransactionDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapSubsidiarySaleOfStockAxis" xlink:to="loc_us-gaapSaleOfStockNameOfTransactionDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IPOMember" xlink:label="loc_us-gaapIPOMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSaleOfStockNameOfTransactionDomain" xlink:to="loc_us-gaapIPOMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srtTitleOfIndividualAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfStockByClassTable" xlink:to="loc_srtTitleOfIndividualAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtTitleOfIndividualAxis" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtTitleOfIndividualAxis" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_MrChensMember" xlink:label="loc_VIOTMrChensMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_VIOTMrChensMember_60" xlink:type="arc" order="63" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardDateAxis" xlink:label="loc_us-gaapAwardDateAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfStockByClassTable" xlink:to="loc_us-gaapAwardDateAxis" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_TwoThousandEighteenMember" xlink:label="loc_VIOTTwoThousandEighteenMember_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAwardDateDomain" xlink:to="loc_VIOTTwoThousandEighteenMember_90" xlink:type="arc" order="93" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueNewIssues_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueNewIssues_150" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues_150" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaapCommonStockSharesAuthorized_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapCommonStockSharesAuthorized_150" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare_150" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapCommonStockSharesOutstanding_150" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaapSharesIssued_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapSharesIssued_150" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaapSharesOutstanding_150" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockLineItems" xlink:to="loc_us-gaapSharesOutstanding_150" xlink:type="arc" order="6" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfCompensationExpenseRecognizedForShare-basedAwardsDetails" xlink:title="999086 - Disclosure - SUMMARY OF COMPENSATION EXPENSE RECOGNIZED FOR SHARE-BASED AWARDS (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfStockOptionActivityDetails" xlink:title="999087 - Disclosure - SUMMARY OF STOCK OPTION ACTIVITY (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/Share-basedCompensationDetailsNarrative" xlink:title="999088 - Disclosure - SHARE-BASED COMPENSATION (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="loc_us-gaapPlanNameAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_TwoThousandFifteenShareIncentivePlanMember" xlink:label="loc_VIOTTwoThousandFifteenShareIncentivePlanMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_VIOTTwoThousandFifteenShareIncentivePlanMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_TwoThousandEighteenShareIncentivePlanMember" xlink:label="loc_VIOTTwoThousandEighteenShareIncentivePlanMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_VIOTTwoThousandEighteenShareIncentivePlanMember_10" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VestingAxis" xlink:label="loc_us-gaapVestingAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="loc_us-gaapVestingAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaapVestingDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapVestingAxis" xlink:to="loc_us-gaapVestingDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaapVestingDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapVestingAxis" xlink:to="loc_us-gaapVestingDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember" xlink:label="loc_us-gaapShareBasedCompensationAwardTrancheOneMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapVestingDomain" xlink:to="loc_us-gaapShareBasedCompensationAwardTrancheOneMember_30" xlink:type="arc" order="32" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember" xlink:label="loc_us-gaapShareBasedCompensationAwardTrancheTwoMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapVestingDomain" xlink:to="loc_us-gaapShareBasedCompensationAwardTrancheTwoMember_40" xlink:type="arc" order="42" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis" xlink:label="loc_deiLegalEntityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="loc_deiLegalEntityAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="loc_deiEntityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_deiLegalEntityAxis" xlink:to="loc_deiEntityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain" xlink:label="loc_deiEntityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_deiLegalEntityAxis" xlink:to="loc_deiEntityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_GuangdongLiziTechnologyCompanyLimitedMember" xlink:label="loc_VIOTGuangdongLiziTechnologyCompanyLimitedMember_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_VIOTGuangdongLiziTechnologyCompanyLimitedMember_120" xlink:type="arc" order="121" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:label="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="loc_srtEquityMethodInvesteeNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:to="loc_srtEquityMethodInvesteeNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="loc_srtEquityMethodInvesteeNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:to="loc_srtEquityMethodInvesteeNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_SunglowWealthHKLimitedMember" xlink:label="loc_VIOTSunglowWealthHKLimitedMember_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtEquityMethodInvesteeNameDomain" xlink:to="loc_VIOTSunglowWealthHKLimitedMember_120" xlink:type="arc" order="122" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_140" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_140" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage" xlink:label="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_140" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_140" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions" xlink:label="loc_us-gaapEmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapEmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_140" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage" xlink:label="loc_us-gaapEquityMethodInvestmentOwnershipPercentage_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapEquityMethodInvestmentOwnershipPercentage_140" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments" xlink:label="loc_us-gaapEquityMethodInvestments_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapEquityMethodInvestments_140" xlink:type="arc" order="6" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfNetIncomePerShareBasicAndDilutedDetails" xlink:title="999089 - Disclosure - SUMMARY OF NET INCOME PER SHARE, BASIC AND DILUTED (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfRelatedPartyTransactionRelationshipDetails" xlink:title="999090 - Disclosure - SUMMARY OF RELATED PARTY TRANSACTION RELATIONSHIP (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:label="loc_us-gaapCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="loc_us-gaapScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="loc_us-gaapScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srtCounterpartyNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:to="loc_srtCounterpartyNameAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_FoshanYunmiElectricAppliancesTechnologyCompanyLimitedMember" xlink:label="loc_VIOTFoshanYunmiElectricAppliancesTechnologyCompanyLimitedMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTFoshanYunmiElectricAppliancesTechnologyCompanyLimitedMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_XiaomiMember" xlink:label="loc_VIOTXiaomiMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTXiaomiMember_10" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDescriptionOfTransaction" xlink:label="loc_us-gaapRelatedPartyTransactionDescriptionOfTransaction_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="loc_us-gaapRelatedPartyTransactionDescriptionOfTransaction_30" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfRelatedPartyTransactionsDetails" xlink:title="999091 - Disclosure - SUMMARY OF RELATED PARTY TRANSACTIONS (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaapRelatedPartyTransactionLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srtCounterpartyNameAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="loc_srtCounterpartyNameAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtCounterpartyNameAxis" xlink:to="loc_srtRepurchaseAgreementCounterpartyNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_XiaomiMember" xlink:label="loc_VIOTXiaomiMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTXiaomiMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_FoshanViomiMember" xlink:label="loc_VIOTFoshanViomiMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtRepurchaseAgreementCounterpartyNameDomain" xlink:to="loc_VIOTFoshanViomiMember_20" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_PurchasePayableToRelatedPartyMember" xlink:label="loc_VIOTPurchasePayableToRelatedPartyMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_VIOTPurchasePayableToRelatedPartyMember_60" xlink:type="arc" order="63" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_CommissionExpensesChargedByRelatedPartyMember" xlink:label="loc_VIOTCommissionExpensesChargedByRelatedPartyMember_140" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_VIOTCommissionExpensesChargedByRelatedPartyMember_140" xlink:type="arc" order="143" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_OtherExpensesChargedByRelatedPartyMember" xlink:label="loc_VIOTOtherExpensesChargedByRelatedPartyMember_160" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_VIOTOtherExpensesChargedByRelatedPartyMember_160" xlink:type="arc" order="163" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent_190" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapAccountsReceivableNetCurrent_190" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivablesNetCurrent" xlink:label="loc_us-gaapOtherReceivablesNetCurrent_190" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapOtherReceivablesNetCurrent_190" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent_190" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapOtherLiabilitiesCurrent_190" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty" xlink:label="loc_us-gaapRelatedPartyTransactionPurchasesFromRelatedParty_190" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapRelatedPartyTransactionPurchasesFromRelatedParty_190" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_190" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_190" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaapSellingAndMarketingExpense_190" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapSellingAndMarketingExpense_190" xlink:type="arc" order="5" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfAssetsMeasuredAtFairValueOnRecurringBasisDetails" xlink:title="999092 - Disclosure - SUMMARY OF ASSETS MEASURED AT FAIR VALUE ON RECURRING BASIS (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:label="loc_us-gaapFairValueOffBalanceSheetRisksDisclosureInformationLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable" xlink:label="loc_us-gaapScheduleOfFairValueOffBalanceSheetRisksTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapFairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:to="loc_us-gaapScheduleOfFairValueOffBalanceSheetRisksTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfFairValueOffBalanceSheetRisksTable" xlink:to="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" xlink:to="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" xlink:to="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaapFairValueInputsLevel1Member_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:to="loc_us-gaapFairValueInputsLevel1Member_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaapFairValueInputsLevel2Member_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:to="loc_us-gaapFairValueInputsLevel2Member_10" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaapFairValueInputsLevel3Member_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:to="loc_us-gaapFairValueInputsLevel3Member_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="loc_us-gaapFairValueByMeasurementFrequencyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfFairValueOffBalanceSheetRisksTable" xlink:to="loc_us-gaapFairValueByMeasurementFrequencyAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="loc_us-gaapFairValueMeasurementFrequencyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFairValueByMeasurementFrequencyAxis" xlink:to="loc_us-gaapFairValueMeasurementFrequencyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="loc_us-gaapFairValueMeasurementFrequencyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapFairValueByMeasurementFrequencyAxis" xlink:to="loc_us-gaapFairValueMeasurementFrequencyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="loc_us-gaapFairValueMeasurementsRecurringMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementFrequencyDomain" xlink:to="loc_us-gaapFairValueMeasurementsRecurringMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure" xlink:label="loc_us-gaapInvestmentsFairValueDisclosure_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:to="loc_us-gaapInvestmentsFairValueDisclosure_90" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfComponentsOfLeaseExpenseDetails" xlink:title="999093 - Disclosure - SUMMARY OF COMPONENTS OF LEASE EXPENSE (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfSupplementalCashFlowInformationForLeasesDetails" xlink:title="999094 - Disclosure - SUMMARY OF SUPPLEMENTAL CASH FLOW INFORMATION FOR LEASES (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfAggregateFutureMinimumRentalPaymentsUnderNon-cancelableAgreementDetails" xlink:title="999095 - Disclosure - SUMMARY OF AGGREGATE FUTURE MINIMUM RENTAL PAYMENTS UNDER NON-CANCELABLE AGREEMENT (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/LeasesDetailsNarrative" xlink:title="999096 - Disclosure - LEASES (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/SummaryOfCapitalAndOtherCommitmentDetails" xlink:title="999097 - Disclosure - SUMMARY OF CAPITAL AND OTHER COMMITMENT (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:title="999098 - Disclosure - COMMITMENTS AND CONTINGENCIES (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/RestrictedNetAssetsDetailsNarrative" xlink:title="999099 - Disclosure - RESTRICTED NET ASSETS (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/UnauditedCondensedParentCompanyBalanceSheetsDetails" xlink:title="999100 - Disclosure - Unaudited Condensed Parent Company Balance Sheets (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CondensedFinancialStatementsCaptionsLineItems" xlink:label="loc_srtCondensedFinancialStatementsCaptionsLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfCondensedFinancialStatementsTable" xlink:label="loc_srtScheduleOfCondensedFinancialStatementsTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember_20" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaapCommonClassBMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassBMember_40" xlink:type="arc" order="42" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaapAssetsAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapAssetsAbstract_70" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_70" xlink:to="loc_us-gaapCashAndCashEquivalentsAtCarryingValue_70" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermInvestments" xlink:label="loc_us-gaapShortTermInvestments_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_70" xlink:to="loc_us-gaapShortTermInvestments_70" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AmountDueFromGroupCompanies" xlink:label="loc_VIOTAmountDueFromGroupCompanies_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_VIOTAmountDueFromGroupCompanies_70" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:label="loc_us-gaapInvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapInvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_70" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssets" xlink:label="loc_us-gaapOtherAssets_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapOtherAssets_70" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapAssets_70" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAbstract" xlink:label="loc_us-gaapLiabilitiesAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapLiabilitiesAbstract_70" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapAccountsPayableCurrent_70" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrentAndNoncurrent" xlink:label="loc_us-gaapAccruedLiabilitiesCurrentAndNoncurrent_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapAccruedLiabilitiesCurrentAndNoncurrent_70" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_AmountDueToGroupCompanies" xlink:label="loc_VIOTAmountDueToGroupCompanies_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_VIOTAmountDueToGroupCompanies_70" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapLiabilities_70" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaapStockholdersEquityAbstract_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapStockholdersEquityAbstract_70" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_70" xlink:to="loc_us-gaapCommonStockValue_70" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValue" xlink:label="loc_us-gaapTreasuryStockValue_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_70" xlink:to="loc_us-gaapTreasuryStockValue_70" xlink:type="arc" order="14" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_70" xlink:to="loc_us-gaapAdditionalPaidInCapital_70" xlink:type="arc" order="15" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_70" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit_70" xlink:type="arc" order="16" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_70" xlink:to="loc_us-gaapStockholdersEquity_70" xlink:type="arc" order="17" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity_70" xlink:type="arc" order="18" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/UnauditedCondensedParentCompanyBalanceSheetsParentheticalDetails" xlink:title="999101 - Disclosure - Unaudited Condensed Parent Company Balance Sheets (Parenthetical) (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CondensedFinancialStatementsCaptionsLineItems" xlink:label="loc_srtCondensedFinancialStatementsCaptionsLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfCondensedFinancialStatementsTable" xlink:label="loc_srtScheduleOfCondensedFinancialStatementsTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaapCommonClassBMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassBMember_20" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare_50" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaapCommonStockSharesAuthorized_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapCommonStockSharesAuthorized_50" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued_50" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapCommonStockSharesOutstanding_50" xlink:type="arc" order="3" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/UnauditedCondensedParentCompanyStatementsOfOperationsDetails" xlink:title="999102 - Disclosure - Unaudited Condensed Parent Company Statements of Operations (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CondensedFinancialStatementsCaptionsLineItems" xlink:label="loc_srtCondensedFinancialStatementsCaptionsLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfCondensedFinancialStatementsTable" xlink:label="loc_srtScheduleOfCondensedFinancialStatementsTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaapOperatingExpensesAbstract_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapOperatingExpensesAbstract_30" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaapGeneralAndAdministrativeExpense_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapGeneralAndAdministrativeExpense_30" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapOperatingExpenses_30" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherOperatingIncomeExpenseNet" xlink:label="loc_us-gaapOtherOperatingIncomeExpenseNet_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapOtherOperatingIncomeExpenseNet_30" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvestee" xlink:label="loc_us-gaapGainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvestee_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapGainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvestee_30" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaapOperatingIncomeLoss_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapOperatingIncomeLoss_30" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="viot-20260630.xsd#VIOT_InterestIncomeExpenseAndShortTermInvestmentsIncomeNonoperatingNet" xlink:label="loc_VIOTInterestIncomeExpenseAndShortTermInvestmentsIncomeNonoperatingNet_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_VIOTInterestIncomeExpenseAndShortTermInvestmentsIncomeNonoperatingNet_30" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_30" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaapIncomeTaxExpenseBenefit_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapIncomeTaxExpenseBenefit_30" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapOperatingExpensesAbstract_30" xlink:to="loc_us-gaapNetIncomeLoss_30" xlink:type="arc" order="9" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://ir.viomi.com/role/UnauditedCondensedParentCompanyStatementsOfCashFlowsDetails" xlink:title="999103 - Disclosure - Unaudited Condensed Parent Company Statements of Cash Flows (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CondensedFinancialStatementsCaptionsLineItems" xlink:label="loc_srtCondensedFinancialStatementsCaptionsLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfCondensedFinancialStatementsTable" xlink:label="loc_srtScheduleOfCondensedFinancialStatementsTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srtScheduleOfCondensedFinancialStatementsTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInOperatingActivities_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapNetCashProvidedByUsedInOperatingActivities_70" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInInvestingActivities_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapNetCashProvidedByUsedInInvestingActivities_70" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInFinancingActivities_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapNetCashProvidedByUsedInFinancingActivities_70" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="loc_us-gaapEffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapEffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_70" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_70" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtCondensedFinancialStatementsCaptionsLineItems" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_70" xlink:type="arc" order="5" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaapIncomeTaxAuthorityDomain" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DomesticCountryMember" xlink:label="loc_us-gaapDomesticCountryMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapIncomeTaxAuthorityDomain" xlink:to="loc_us-gaapDomesticCountryMember" xlink:type="arc" order="1000" />
    </link:definitionLink>
</link:linkbase>
