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        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001308676</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



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    <formData>
        <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>MICHAEL HSING</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
                <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>8000</noOfUnitsSold>
            <aggregateMarketValue>5848608.80</aggregateMarketValue>
            <noOfUnitsOutstanding>48672000</noOfUnitsOutstanding>
            <approxSaleDate>06/03/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>02/03/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>2183</amountOfSecuritiesAcquired>
            <paymentDate>02/03/2024</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>05/07/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1554</amountOfSecuritiesAcquired>
            <paymentDate>05/07/2024</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>02/07/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>4263</amountOfSecuritiesAcquired>
            <paymentDate>02/07/2024</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>MICHAEL HSING</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                    <ns2:city>Kirkland</ns2:city>
                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>05/08/2024</saleDate>
            <amountOfSecuritiesSold>2823</amountOfSecuritiesSold>
            <grossProceeds>1947869.81</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>MICHAEL HSING</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                    <ns2:city>Kirkland</ns2:city>
                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>05/01/2024</saleDate>
            <amountOfSecuritiesSold>8000</amountOfSecuritiesSold>
            <grossProceeds>5294837.60</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>MICHAEL HSING</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                    <ns2:city>Kirkland</ns2:city>
                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>04/01/2024</saleDate>
            <amountOfSecuritiesSold>8000</amountOfSecuritiesSold>
            <grossProceeds>5419520.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>06/03/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>08/23/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Michael Hsing</signature>
        </noticeSignature>
    </formData>
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144
0001308676
XXXXXXXX
LIVE
0001280452
MONOLITHIC POWER SYSTEMS, INC.
000-51026
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
(425) 296-9956
MICHAEL HSING
Officer
Director
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
8000
5848608.80
48672000
06/03/2024
NASDAQ
COMMON
02/03/2024
Performance Shares
ISSUER
N
2183
02/03/2024
Not Applicable
COMMON
05/07/2024
Performance Shares
ISSUER
N
1554
05/07/2024
Not Applicable
COMMON
02/07/2024
Performance Shares
ISSUER
N
4263
02/07/2024
Not Applicable
N
MICHAEL HSING
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
05/08/2024
2823
1947869.81
MICHAEL HSING
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
05/01/2024
8000
5294837.60
MICHAEL HSING
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
04/01/2024
8000
5419520.00
06/03/2024
08/23/2023
/s/ Michael Hsing