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                    <ccc>XXXXXXXX</ccc>
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            <liveTestFlag>LIVE</liveTestFlag>



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        <issuerInfo>
            <issuerCik>0001785173</issuerCik>
            <issuerName>89BIO, INC.</issuerName>
            <secFileNumber>001-39122</secFileNumber>
            <issuerAddress>
                <ns2:street1>142 Sansome Street 2nd Floor</ns2:street1>
                <ns2:city>San Francisco</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>94104</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(415) 432-9270</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>EDWARD M ATKINSON</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Director</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>E*TRADE FINANCIAL CORPORATION</name>
                <address>
                    <ns2:street1>3 EDISON DRIVE</ns2:street1>
                    <ns2:city>ALPHARETTA</ns2:city>
                    <ns2:stateOrCountry>GA</ns2:stateOrCountry>
                    <ns2:zipCode>30005</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>6250</noOfUnitsSold>
            <aggregateMarketValue>111960.63</aggregateMarketValue>
            <noOfUnitsOutstanding>72868455</noOfUnitsOutstanding>
            <approxSaleDate>06/01/2023</approxSaleDate>
            <securitiesExchangeName>NASD</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>06/01/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>6250</amountOfSecuritiesAcquired>
            <paymentDate>06/01/2023</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>06/01/2023</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>01/30/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>EDWARD M ATKINSON</signature>
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144
0001914164
XXXXXXXX
LIVE
0001785173
89BIO, INC.
001-39122
142 Sansome Street 2nd Floor
San Francisco
CA
94104
(415) 432-9270
EDWARD M ATKINSON
Director
Common
E*TRADE FINANCIAL CORPORATION
3 EDISON DRIVE
ALPHARETTA
GA
30005
6250
111960.63
72868455
06/01/2023
NASD
Common
06/01/2023
Stock Option Exercise
Issuer
N
6250
06/01/2023
Cash
Y
06/01/2023
01/30/2023
EDWARD M ATKINSON