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      <link:roleType id="DEBTDetailsTextuals" roleURI="http://www.heico.com/role/DEBTDetailsTextuals">
        <link:definition>9955537 - Disclosure - DEBT (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>9955538 - Disclosure - REVENUE (Contract Assets and Liabilities) (Details)</link:definition>
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      <link:roleType id="REVENUEDisaggregationofRevenuebyProductLineDetails" roleURI="http://www.heico.com/role/REVENUEDisaggregationofRevenuebyProductLineDetails">
        <link:definition>9955539 - Disclosure - REVENUE (Disaggregation of Revenue, by Product Line) (Details)</link:definition>
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      <link:roleType id="REVENUEDisaggregationofRevenuebyIndustryDetails" roleURI="http://www.heico.com/role/REVENUEDisaggregationofRevenuebyIndustryDetails">
        <link:definition>9955540 - Disclosure - REVENUE (Disaggregation of Revenue, by Industry) (Details)</link:definition>
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      <link:roleType id="REVENUEDetailsTextuals" roleURI="http://www.heico.com/role/REVENUEDetailsTextuals">
        <link:definition>9955541 - Disclosure - REVENUE (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="REVENUEDetailsTextuals_1" roleURI="http://www.heico.com/role/REVENUEDetailsTextuals_1">
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="INCOMETAXESDetailsTextuals" roleURI="http://www.heico.com/role/INCOMETAXESDetailsTextuals">
        <link:definition>9955542 - Disclosure - INCOME TAXES (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="FAIRVALUEMEASUREMENTSFairValueHierarchybyCategoryDetails" roleURI="http://www.heico.com/role/FAIRVALUEMEASUREMENTSFairValueHierarchybyCategoryDetails">
        <link:definition>9955543 - Disclosure - FAIR VALUE MEASUREMENTS (Fair Value Hierarchy, by Category) (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="FAIRVALUEMEASUREMENTSFAIRVALUEMEASUREMENTSLevel3ValuationInputsDetails" roleURI="http://www.heico.com/role/FAIRVALUEMEASUREMENTSFAIRVALUEMEASUREMENTSLevel3ValuationInputsDetails">
        <link:definition>9955544 - Disclosure - FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS (Level 3 Valuation Inputs) (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="FAIRVALUEMEASUREMENTSContingentConsiderationLiabilityDetails" roleURI="http://www.heico.com/role/FAIRVALUEMEASUREMENTSContingentConsiderationLiabilityDetails">
        <link:definition>9955545 - Disclosure - FAIR VALUE MEASUREMENTS (Contingent Consideration Liability) (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="FAIRVALUEMEASUREMENTSDetailsTextuals" roleURI="http://www.heico.com/role/FAIRVALUEMEASUREMENTSDetailsTextuals">
        <link:definition>9955546 - Disclosure - FAIR VALUE MEASUREMENTS (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="NETINCOMEPERSHAREATTRIBUTABLETOHEICOSHAREHOLDERSDetails" roleURI="http://www.heico.com/role/NETINCOMEPERSHAREATTRIBUTABLETOHEICOSHAREHOLDERSDetails">
        <link:definition>9955547 - Disclosure - NET INCOME PER SHARE ATTRIBUTABLE TO HEICO SHAREHOLDERS (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType id="OPERATINGSEGMENTSDetails" roleURI="http://www.heico.com/role/OPERATINGSEGMENTSDetails">
        <link:definition>9955548 - Disclosure - OPERATING SEGMENTS (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OPERATINGSEGMENTSAssetsDetails" roleURI="http://www.heico.com/role/OPERATINGSEGMENTSAssetsDetails">
        <link:definition>9955549 - Disclosure - OPERATING SEGMENTS (Assets) (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OPERATINGSEGMENTSDetailsTextuals" roleURI="http://www.heico.com/role/OPERATINGSEGMENTSDetailsTextuals">
        <link:definition>9955550 - Disclosure - OPERATING SEGMENTS (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="COMMITMENTSANDCONTINGENCIESDetails" roleURI="http://www.heico.com/role/COMMITMENTSANDCONTINGENCIESDetails">
        <link:definition>9955551 - Disclosure - COMMITMENTS AND CONTINGENCIES (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType id="COMMITMENTSANDCONTINGENCIESDetailsTextuals" roleURI="http://www.heico.com/role/COMMITMENTSANDCONTINGENCIESDetailsTextuals">
        <link:definition>9955552 - Disclosure - COMMITMENTS AND CONTINGENCIES (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType id="SubsequentEventsDetailsTextuals" roleURI="http://www.heico.com/role/SubsequentEventsDetailsTextuals">
        <link:definition>9955553 - Disclosure - Subsequent Events (Details Textuals)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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  <xs:element id="hei_SegmentReportingReconcilingItemForOperatingProfitLossAndCapitalExpenditureFromSegmentToConsolidatedLineItems" abstract="true" name="SegmentReportingReconcilingItemForOperatingProfitLossAndCapitalExpenditureFromSegmentToConsolidatedLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="hei_ScheduleofProductWarrantiesTable" abstract="true" name="ScheduleofProductWarrantiesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="hei_ProductWarrantyLiabilityAxis" abstract="true" name="ProductWarrantyLiabilityAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="hei_ProductWarrantyLiabilityDomain" abstract="true" name="ProductWarrantyLiabilityDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="hei_ScheduleofProductWarrantiesLineItems" abstract="true" name="ScheduleofProductWarrantiesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="hei_PotentialAcquisitionMember" abstract="true" name="PotentialAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
