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    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001729765</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
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  <formData>
    <issuerInfo>
      <issuerCik>0001145255</issuerCik>
      <issuerName>HENNESSY ADVISORS INC</issuerName>
      <secFileNumber>001-36423</secFileNumber>
      <issuerAddress>
        <com:street1>7250 REDWOOD BLVD.</com:street1>
        <com:street2>SUITE 200</com:street2>
        <com:city>NOVATO</com:city>
        <com:stateOrCountry>CA</com:stateOrCountry>
        <com:zipCode>94945</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>415-899-1555</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Fahy Kathryn</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Charles Schwab Corporation</name>
        <address>
          <com:street1>3000 Schwab Way</com:street1>
          <com:city>Westlake</com:city>
          <com:stateOrCountry>TX</com:stateOrCountry>
          <com:zipCode>76262</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>8000</noOfUnitsSold>
      <aggregateMarketValue>88000.00</aggregateMarketValue>
      <noOfUnitsOutstanding>7783737</noOfUnitsOutstanding>
      <approxSaleDate>02/27/2025</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>09/18/2024</acquiredDate>
      <natureOfAcquisitionTransaction>RSU vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>10625</amountOfSecuritiesAcquired>
      <paymentDate>09/18/2024</paymentDate>
      <natureOfPayment>Issued as part of restricted stock vesting schedule</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>02/27/2025</noticeDate>
      <signature>KATHRYN FAHY</signature>
    </noticeSignature>
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144
0001729765
XXXXXXXX
LIVE
0001145255
HENNESSY ADVISORS INC
001-36423
7250 REDWOOD BLVD.
SUITE 200
NOVATO
CA
94945
415-899-1555
Fahy Kathryn
Officer
Common
Charles Schwab Corporation
3000 Schwab Way
Westlake
TX
76262
8000
88000.00
7783737
02/27/2025
NASDAQ
Common
09/18/2024
RSU vesting
Issuer
N
10625
09/18/2024
Issued as part of restricted stock vesting schedule
Y
02/27/2025
KATHRYN FAHY