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        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001292133</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



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        <issuerInfo>
            <issuerCik>0001280452</issuerCik>
            <issuerName>MONOLITHIC POWER SYSTEMS, INC.</issuerName>
            <secFileNumber>000-51026</secFileNumber>
            <issuerAddress>
                <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                <ns2:city>Kirkland</ns2:city>
                <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                <ns2:zipCode>98033</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(425) 296-9956</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>VICTOR LEE</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Director</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>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>1000</noOfUnitsSold>
            <aggregateMarketValue>820460.00</aggregateMarketValue>
            <noOfUnitsOutstanding>48672000</noOfUnitsOutstanding>
            <approxSaleDate>06/28/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>02/08/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>542</amountOfSecuritiesAcquired>
            <paymentDate>02/08/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>02/02/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>458</amountOfSecuritiesAcquired>
            <paymentDate>02/02/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>06/28/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>02/28/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Victor Lee</signature>
        </noticeSignature>
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144
0001292133
XXXXXXXX
LIVE
0001280452
MONOLITHIC POWER SYSTEMS, INC.
000-51026
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
(425) 296-9956
VICTOR LEE
Director
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
1000
820460.00
48672000
06/28/2024
NASDAQ
COMMON
02/08/2023
Restricted Stock
ISSUER
N
542
02/08/2023
Not Applicable
COMMON
02/02/2022
Restricted Stock
ISSUER
N
458
02/02/2022
Not Applicable
Y
06/28/2024
02/28/2024
/s/ Victor Lee