content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
    <headerData>
      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001191733</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0000350894</issuerCik>
        <issuerName>SEI INVESTMENTS COMPANY</issuerName>
        <secFileNumber>000-10200</secFileNumber>
        <issuerAddress>
          <com:street1>1 Freedom Valley Drive</com:street1>
          <com:city>Oaks</com:city>
          <com:stateOrCountry>PA</com:stateOrCountry>
          <com:zipCode>19456</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>(610) 676-1000</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>WITHROW WAYNE</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Morgan Stanley Smith Barney LLC</name>
          <address>
            <com:street1>Executive Financial Services</com:street1>
            <com:street2>1 New York Plaza, 38th Floor</com:street2>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10004</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>40000</noOfUnitsSold>
        <aggregateMarketValue>2635648.00</aggregateMarketValue>
        <noOfUnitsOutstanding>131587693</noOfUnitsOutstanding>
        <approxSaleDate>02/05/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>02/05/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Exercise of options under a registered plan</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>40000</amountOfSecuritiesAcquired>
        <paymentDate>02/05/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <securitiesSoldInPast3Months>
        <sellerDetails>
          <name>Wayne M Withrow</name>
          <address>
            <com:street1>1 Freedom Valley Drive</com:street1>
            <com:city>Oaks</com:city>
            <com:stateOrCountry>PA</com:stateOrCountry>
            <com:zipCode>19456</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <saleDate>11/21/2023</saleDate>
        <amountOfSecuritiesSold>8924</amountOfSecuritiesSold>
        <grossProceeds>517592.00</grossProceeds>
      </securitiesSoldInPast3Months>
      <remarks>This Form 144 is being filed for the cashless exercise of options and subsequent sales of the underlying shares commencing on 02/05/2024</remarks>
      <noticeSignature>
        <noticeDate>02/05/2024</noticeDate>
        <signature>/s/ Wayne M Withrow</signature>
      </noticeSignature>
    </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 3560}]
text: 144
  0001191733
  XXXXXXXX
  LIVE
  0000350894
  SEI INVESTMENTS COMPANY
  000-10200
  1 Freedom Valley Drive
  Oaks
  PA
  19456
  (610) 676-1000
  WITHROW WAYNE
  Officer
  Common
  Morgan Stanley Smith Barney LLC
  Executive Financial Services
  1 New York Plaza, 38th Floor
  New York
  NY
  10004
  40000
  2635648.00
  131587693
  02/05/2024
  NASDAQ
  Common
  02/05/2024
  Exercise of options under a registered plan
  Issuer
  N
  40000
  02/05/2024
  Cash
  N
  Wayne M Withrow
  1 Freedom Valley Drive
  Oaks
  PA
  19456
  Common
  11/21/2023
  8924
  517592.00
  This Form 144 is being filed for the cashless exercise of options and subsequent sales of the underlying shares commencing on 02/05/2024
  02/05/2024
  /s/ Wayne M Withrow