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  <xs:element id="htgc_ScheduleOfLoanExitFeesReceivableTableTextBlock" abstract="false" name="ScheduleOfLoanExitFeesReceivableTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="htgc_WeMayBeExposedToHigherRisksWithRespectToOurInvestmentsThatIncludePikInterestOrExitFeesMember" abstract="true" name="WeMayBeExposedToHigherRisksWithRespectToOurInvestmentsThatIncludePikInterestOrExitFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_SixMonthSecuredOvernightFinancingRateSOFROvernightIndexSwapRateMember" abstract="true" name="SixMonthSecuredOvernightFinancingRateSOFROvernightIndexSwapRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_UnamortizedFeeIncome" abstract="false" name="UnamortizedFeeIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="htgc_WeMayExperienceFluctuationsInOurOperatingResultsMember" abstract="true" name="WeMayExperienceFluctuationsInOurOperatingResultsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_InformationServicesMember" abstract="true" name="InformationServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_ValuationTechniqueMarketComparableCompaniesMember" abstract="true" name="ValuationTechniqueMarketComparableCompaniesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_BaseDividendMember" abstract="true" name="BaseDividendMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_SoftwareMember" abstract="true" name="SoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_MarchTwoThousandTwentySixANotesMember" abstract="true" name="MarchTwoThousandTwentySixANotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_PerformanceVestingAwardMember" abstract="true" name="PerformanceVestingAwardMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_WeAreSubjectToRisksRelatedToCorporateSocialResponsibilityMember" abstract="true" name="WeAreSubjectToRisksRelatedToCorporateSocialResponsibilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_TheNotesMayOrMayNotHaveAnEstablishedTradingMarketIfATradingMarketInTheNotesIsDevelopedItMayNotBeMaintainedMember" abstract="true" name="TheNotesMayOrMayNotHaveAnEstablishedTradingMarketIfATradingMarketInTheNotesIsDevelopedItMayNotBeMaintainedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_ThePhaseOutAndReplacementOfLIBORMayAdverselyAffectTheValueOfOurPortfolioSecuritiesMember" abstract="true" name="ThePhaseOutAndReplacementOfLIBORMayAdverselyAffectTheValueOfOurPortfolioSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_EnmarkSystemsIncMember" abstract="true" name="EnmarkSystemsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThree" abstract="false" name="LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThree" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="htgc_BrainCorporationMember" abstract="true" name="BrainCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_SpilloveramountpershareMember" abstract="true" name="SpilloveramountpershareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_InvestmentCompanyCapitalShareTransactionIncreaseDecreasePerShare" abstract="false" name="InvestmentCompanyCapitalShareTransactionIncreaseDecreasePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="htgc_IncludingCashAndCashEquivalentsAndDerivativeInstrumentsMember" abstract="true" name="IncludingCashAndCashEquivalentsAndDerivativeInstrumentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_CerosIncMember" abstract="true" name="CerosIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_UnfundedCommitmentsDueInOneYear" abstract="false" name="UnfundedCommitmentsDueInOneYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="htgc_UnfundedCommitmentsDueInPriorYear" abstract="false" name="UnfundedCommitmentsDueInPriorYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="htgc_MediaContentInfoMember" abstract="true" name="MediaContentInfoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_AxsomeTherapeuticsIncMember" abstract="true" name="AxsomeTherapeuticsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_OperatingUnderTheConstraintsImposedOnUsAsABdcAndRicMayHinderTheAchievementOfOurInvestmentObjectivesMember" abstract="true" name="OperatingUnderTheConstraintsImposedOnUsAsABdcAndRicMayHinderTheAchievementOfOurInvestmentObjectivesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_BiotechnologyToolsMember" abstract="true" name="BiotechnologyToolsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_CheckrGroupIncMember" abstract="true" name="CheckrGroupIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_AltumintIncMember" abstract="true" name="AltumintIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_PromissoryNotesMember" abstract="true" name="PromissoryNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_EquityAndWarrantInvestmentsMember" abstract="true" name="EquityAndWarrantInvestmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_DragosMember" abstract="true" name="DragosMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="htgc_EquityOfferingExpensesPolicyPolicyPolicyTextBlock" abstract="false" name="EquityOfferingExpensesPolicyPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="htgc_AdviserFundsMember" abstract="true" name="AdviserFundsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_IfWeDefaultOnOurObligationsImposedUponUsByOurIndebtednessWeMayNotBeAbleToMakePaymentsOnOurOutstandingNotesAndCreditFacilitiesMember" abstract="true" name="IfWeDefaultOnOurObligationsImposedUponUsByOurIndebtednessWeMayNotBeAbleToMakePaymentsOnOurOutstandingNotesAndCreditFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_RealizedGainLossMember" abstract="true" name="RealizedGainLossMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_UnvestedRestrictedStockAwardsMember" abstract="true" name="UnvestedRestrictedStockAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_IndustrySubSectorConcentrationRiskMember" abstract="true" name="IndustrySubSectorConcentrationRiskMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_FailureToMaintainOurStatusAsABdcWouldReduceOurOperatingFlexibilityMember" abstract="true" name="FailureToMaintainOurStatusAsABdcWouldReduceOurOperatingFlexibilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="htgc_DividendIncomeMember" abstract="true" name="DividendIncomeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
