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        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001920738</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001650648</issuerCik>
            <issuerName>4D MOLECULAR THERAPEUTICS INC</issuerName>
            <secFileNumber>001-39782</secFileNumber>
            <issuerAddress>
                <ns2:street1>5858 Horton Street, #455</ns2:street1>
                <ns2:city>Emeryville</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>94608</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>5105052680</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>SCOTT BIZILY</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>13403</noOfUnitsSold>
            <aggregateMarketValue>427019.58</aggregateMarketValue>
            <noOfUnitsOutstanding>49778127</noOfUnitsOutstanding>
            <approxSaleDate>04/01/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>04/01/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>13403</amountOfSecuritiesAcquired>
            <paymentDate>04/01/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for SCOTT BIZILY</name>
                <address>
                    <ns2:street1>5858 Horton Street, #455</ns2:street1>
                    <ns2:city>Emeryville</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94608</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>03/27/2024</saleDate>
            <amountOfSecuritiesSold>5833</amountOfSecuritiesSold>
            <grossProceeds>204410.74</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for SCOTT BIZILY</name>
                <address>
                    <ns2:street1>5858 Horton Street, #455</ns2:street1>
                    <ns2:city>Emeryville</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94608</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>03/18/2024</saleDate>
            <amountOfSecuritiesSold>1750</amountOfSecuritiesSold>
            <grossProceeds>54722.50</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for SCOTT BIZILY</name>
                <address>
                    <ns2:street1>5858 Horton Street, #455</ns2:street1>
                    <ns2:city>Emeryville</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94608</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>02/27/2024</saleDate>
            <amountOfSecuritiesSold>1909</amountOfSecuritiesSold>
            <grossProceeds>57270.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for SCOTT BIZILY</name>
                <address>
                    <ns2:street1>5858 Horton Street, #455</ns2:street1>
                    <ns2:city>Emeryville</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94608</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>02/16/2024</saleDate>
            <amountOfSecuritiesSold>1750</amountOfSecuritiesSold>
            <grossProceeds>48422.50</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for SCOTT BIZILY</name>
                <address>
                    <ns2:street1>5858 Horton Street, #455</ns2:street1>
                    <ns2:city>Emeryville</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>94608</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>02/08/2024</saleDate>
            <amountOfSecuritiesSold>6244</amountOfSecuritiesSold>
            <grossProceeds>171710.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <remarks>The securities to be sold were and will be received upon the exercise of stock options over the next three months.
</remarks>
        <noticeSignature>
            <noticeDate>04/01/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>10/10/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Scott Bizily</signature>
        </noticeSignature>
    </formData>
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144
0001920738
XXXXXXXX
LIVE
0001650648
4D MOLECULAR THERAPEUTICS INC
001-39782
5858 Horton Street, #455
Emeryville
CA
94608
5105052680
SCOTT BIZILY
Officer
COMMON
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
13403
427019.58
49778127
04/01/2024
NASDAQ
Common
04/01/2024
Exercise of Stock Options
Issuer
N
13403
04/01/2024
Cash
N
10b5-1 Sales for SCOTT BIZILY
5858 Horton Street, #455
Emeryville
CA
94608
COMMON
03/27/2024
5833
204410.74
10b5-1 Sales for SCOTT BIZILY
5858 Horton Street, #455
Emeryville
CA
94608
COMMON
03/18/2024
1750
54722.50
10b5-1 Sales for SCOTT BIZILY
5858 Horton Street, #455
Emeryville
CA
94608
COMMON
02/27/2024
1909
57270.00
10b5-1 Sales for SCOTT BIZILY
5858 Horton Street, #455
Emeryville
CA
94608
COMMON
02/16/2024
1750
48422.50
10b5-1 Sales for SCOTT BIZILY
5858 Horton Street, #455
Emeryville
CA
94608
COMMON
02/08/2024
6244
171710.00
The securities to be sold were and will be received upon the exercise of stock options over the next three months.
04/01/2024
10/10/2023
/s/ Scott Bizily