<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:ns2="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>
                <ns2:street1>1 Freedom Valley Drive</ns2:street1>
                <ns2:city>Oaks</ns2:city>
                <ns2:stateOrCountry>PA</ns2:stateOrCountry>
                <ns2:zipCode>19456-1100</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(610) 676-1000</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>WAYNE M WITHROW</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>38th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>8924</noOfUnitsSold>
            <aggregateMarketValue>517592.00</aggregateMarketValue>
            <noOfUnitsOutstanding>131587693</noOfUnitsOutstanding>
            <approxSaleDate>11/21/2023</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/21/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of options under a registered plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>8924</amountOfSecuritiesAcquired>
            <paymentDate>11/21/2023</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>Wayne Withrow</name>
                <address>
                    <ns2:street1>1 Freedom Valley Drive</ns2:street1>
                    <ns2:city>Oaks</ns2:city>
                    <ns2:stateOrCountry>PA</ns2:stateOrCountry>
                    <ns2:zipCode>19456-1100</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>09/20/2023</saleDate>
            <amountOfSecuritiesSold>10000</amountOfSecuritiesSold>
            <grossProceeds>619728.07</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>Wayne Withrow</name>
                <address>
                    <ns2:street1>1 Freedom Valley Drive</ns2:street1>
                    <ns2:city>Oaks</ns2:city>
                    <ns2:stateOrCountry>PA</ns2:stateOrCountry>
                    <ns2:zipCode>19456-1100</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>09/19/2023</saleDate>
            <amountOfSecuritiesSold>1076</amountOfSecuritiesSold>
            <grossProceeds>66413.95</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>11/21/2023</noticeDate>
            <planAdoptionDates/>
            <signature>/s/ Wayne M Withrow</signature>
        </noticeSignature>
    </formData>
</edgarSubmission>
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144
0001191733
XXXXXXXX
LIVE
0000350894
SEI INVESTMENTS COMPANY
000-10200
1 Freedom Valley Drive
Oaks
PA
19456-1100
(610) 676-1000
WAYNE M WITHROW
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
38th Floor
New York
NY
10004
8924
517592.00
131587693
11/21/2023
NASDAQ
Common
11/21/2023
Exercise of options under a registered plan
Issuer
N
8924
11/21/2023
Cash
N
Wayne Withrow
1 Freedom Valley Drive
Oaks
PA
19456-1100
Common
09/20/2023
10000
619728.07
Wayne Withrow
1 Freedom Valley Drive
Oaks
PA
19456-1100
Common
09/19/2023
1076
66413.95
11/21/2023
/s/ Wayne M Withrow