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        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001312593</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <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>SARIA TSENG</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>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>37093</noOfUnitsSold>
            <aggregateMarketValue>29978636.14</aggregateMarketValue>
            <noOfUnitsOutstanding>48672000</noOfUnitsOutstanding>
            <approxSaleDate>07/01/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/07/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>2656</amountOfSecuritiesAcquired>
            <paymentDate>11/07/2021</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/11/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>2120</amountOfSecuritiesAcquired>
            <paymentDate>02/11/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>05/03/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1495</amountOfSecuritiesAcquired>
            <paymentDate>05/03/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>03/31/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>6380</amountOfSecuritiesAcquired>
            <paymentDate>03/31/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>12/31/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>6495</amountOfSecuritiesAcquired>
            <paymentDate>12/31/2021</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/03/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1497</amountOfSecuritiesAcquired>
            <paymentDate>08/03/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/11/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>2129</amountOfSecuritiesAcquired>
            <paymentDate>08/11/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/07/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>10448</amountOfSecuritiesAcquired>
            <paymentDate>02/07/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/03/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1758</amountOfSecuritiesAcquired>
            <paymentDate>02/03/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>02/11/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>2099</amountOfSecuritiesAcquired>
            <paymentDate>02/11/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/15/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Employee Stock Purchase Plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>16</amountOfSecuritiesAcquired>
            <paymentDate>08/15/2022</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</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>11</amountOfSecuritiesSold>
            <grossProceeds>7603.90</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</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>858</amountOfSecuritiesSold>
            <grossProceeds>592020.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>07/01/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>02/29/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Saria Tseng</signature>
        </noticeSignature>
    </formData>
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144
0001312593
XXXXXXXX
LIVE
0001280452
MONOLITHIC POWER SYSTEMS, INC.
000-51026
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
(425) 296-9956
SARIA TSENG
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
37093
29978636.14
48672000
07/01/2024
NASDAQ
Common
11/07/2021
Performance Shares
Issuer
N
2656
11/07/2021
Not Applicable
Common
02/11/2023
Performance Shares
Issuer
N
2120
02/11/2023
Not Applicable
Common
05/03/2022
Performance Shares
Issuer
N
1495
05/03/2022
Not Applicable
Common
03/31/2022
Performance Shares
Issuer
N
6380
03/31/2022
Not Applicable
Common
12/31/2021
Performance Shares
Issuer
N
6495
12/31/2021
Not Applicable
Common
08/03/2022
Performance Shares
Issuer
N
1497
08/03/2022
Not Applicable
Common
08/11/2022
Performance Shares
Issuer
N
2129
08/11/2022
Not Applicable
Common
02/07/2023
Performance Shares
Issuer
N
10448
02/07/2023
Not Applicable
Common
02/03/2023
Performance Shares
Issuer
N
1758
02/03/2023
Not Applicable
Common
02/11/2022
Performance Shares
Issuer
N
2099
02/11/2022
Not Applicable
Common
08/15/2022
Employee Stock Purchase Plan
Issuer
N
16
08/15/2022
Cash
N
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
COMMON
05/08/2024
11
7603.90
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
COMMON
05/08/2024
858
592020.00
07/01/2024
02/29/2024
/s/ Saria Tseng