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  <liveTestFlag>LIVE</liveTestFlag>
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  <issuerName>UNITY Biotechnology, Inc.</issuerName>
  <secFileNumber>001-38470</secFileNumber>
  <issuerAddress>
  <street1 xmlns="http://www.sec.gov/edgar/common">285 E. Grand Ave</street1>
  <city xmlns="http://www.sec.gov/edgar/common">South San Francisco</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">CA</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">94080</zipCode>
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  <issuerContactPhone>650-416-1192</issuerContactPhone>
  <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Anirvan Ghosh</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
  <relationshipsToIssuer>
  <relationshipToIssuer>Officer</relationshipToIssuer>
  </relationshipsToIssuer>
  </issuerInfo>
  <securitiesInformation>
  <securitiesClassTitle>Common Stock</securitiesClassTitle>
  <brokerOrMarketmakerDetails>
  <name>E*TRADE Securities LLC</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">Harborside 2</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">200 Hudson Street, Ste. 501</street2>
  <city xmlns="http://www.sec.gov/edgar/common">Jersey City,</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">NJ</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">07311</zipCode>
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  <noOfUnitsSold>588</noOfUnitsSold>
  <aggregateMarketValue>1275.97</aggregateMarketValue>
  <noOfUnitsOutstanding>87458</noOfUnitsOutstanding>
  <approxSaleDate>05/02/2023</approxSaleDate>
  <securitiesExchangeName>NASDAQ</securitiesExchangeName>
  </securitiesInformation>
  <securitiesToBeSold>
  <securitiesClassTitle>Common Stock</securitiesClassTitle>
  <acquiredDate>05/01/2023</acquiredDate>
  <natureOfAcquisitionTransaction>Restricted Stock Units granted in 2022 under the Issuer's 2018 Incentive Award Plan</natureOfAcquisitionTransaction>
  <nameOfPersonfromWhomAcquired>UNITY Biotechnology, Inc.</nameOfPersonfromWhomAcquired>
  <isGiftTransaction>N</isGiftTransaction>
  <amountOfSecuritiesAcquired>588</amountOfSecuritiesAcquired>
  <paymentDate>05/01/2023</paymentDate>
  <natureOfPayment>N/A</natureOfPayment>
  </securitiesToBeSold>
  <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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  <name>Anirvan Ghosh</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">c/o UNITY Biotechnology, Inc.</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">285 E. Grand Ave.</street2>
  <city xmlns="http://www.sec.gov/edgar/common">South San Francisco</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">CA</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">94080</zipCode>
  </address>
  </sellerDetails>
  <securitiesClassTitle>Restricted Stock Units granted in 2022 under Issuer's 2018 Incentive Award Plan</securitiesClassTitle>
  <saleDate>02/02/2023</saleDate>
  <amountOfSecuritiesSold>2573</amountOfSecuritiesSold>
  <grossProceeds>12453.32</grossProceeds>
  </securitiesSoldInPast3Months>
  <securitiesSoldInPast3Months>
  <sellerDetails>
  <name>Anirvan Ghosh</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">c/o UNITY Biotechnology, Inc.</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">285 E. Grand Ave.</street2>
  <city xmlns="http://www.sec.gov/edgar/common">South San Francisco</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">CA</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">94080</zipCode>
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  </sellerDetails>
  <securitiesClassTitle>Restricted Stock Units granted in 2020 under Issuer's 2018 Incentive Award Plan</securitiesClassTitle>
  <saleDate>03/14/2023</saleDate>
  <amountOfSecuritiesSold>1210</amountOfSecuritiesSold>
  <grossProceeds>4840.00</grossProceeds>
  </securitiesSoldInPast3Months>
  <securitiesSoldInPast3Months>
  <sellerDetails>
  <name>Anirvan Ghosh</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">c/o UNITY Biotechnology, Inc.</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">285 E. Grand Ave.</street2>
  <city xmlns="http://www.sec.gov/edgar/common">South San Francisco</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">CA</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">94080</zipCode>
  </address>
  </sellerDetails>
  <securitiesClassTitle>Restricted Stock Units granted in 2020 under the Issuer's 2020 Incentive Award Plan</securitiesClassTitle>
  <saleDate>03/31/2023</saleDate>
  <amountOfSecuritiesSold>1959</amountOfSecuritiesSold>
  <grossProceeds>3330.30</grossProceeds>
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  <securitiesSoldInPast3Months>
  <sellerDetails>
  <name>Anirvan Ghosh</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">c/o UNITY Biotechnology, Inc.</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">285 E. Grand Ave.</street2>
  <city xmlns="http://www.sec.gov/edgar/common">South San Francisco</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">CA</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">94080</zipCode>
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  <securitiesClassTitle>Restricted Stock Units granted in 2021 under the Issuer's 2018 Incentive Award Plan</securitiesClassTitle>
  <saleDate>05/01/2023</saleDate>
  <amountOfSecuritiesSold>1020</amountOfSecuritiesSold>
  <grossProceeds>2193.00</grossProceeds>
  </securitiesSoldInPast3Months>
  <remarks>1. Share number reflects post-split units before 1-for-10 reverse stock split as of 10/19/22 2Share number reflects pre-split units before 1-for-10 reverse stock split as of 10/19/22</remarks>
  <noticeSignature>
  <noticeDate>05/03/2023</noticeDate>
  <planAdoptionDates>
  <planAdoptionDate>10/02/2021</planAdoptionDate>
  </planAdoptionDates>
  <signature>Alexander Nguyen as attorney-in-fact for Anirvan Ghosh pursuant to Power of Attorney</signature>
  </noticeSignature>
  </formData>
  </edgarSubmission>
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text: 144
  0001807437
  XXXXXXXX
  LIVE
  0001463361
  UNITY Biotechnology, Inc.
  001-38470
  285 E. Grand Ave
  South San Francisco
  CA
  94080
  650-416-1192
  Anirvan Ghosh
  Officer
  Common Stock
  E*TRADE Securities LLC
  Harborside 2
  200 Hudson Street, Ste. 501
  Jersey City,
  NJ
  07311
  588
  1275.97
  87458
  05/02/2023
  NASDAQ
  Common Stock
  05/01/2023
  Restricted Stock Units granted in 2022 under the Issuer's 2018 Incentive Award Plan
  UNITY Biotechnology, Inc.
  N
  588
  05/01/2023
  N/A
  N
  Anirvan Ghosh
  c/o UNITY Biotechnology, Inc.
  285 E. Grand Ave.
  South San Francisco
  CA
  94080
  Restricted Stock Units granted in 2022 under Issuer's 2018 Incentive Award Plan
  02/02/2023
  2573
  12453.32
  Anirvan Ghosh
  c/o UNITY Biotechnology, Inc.
  285 E. Grand Ave.
  South San Francisco
  CA
  94080
  Restricted Stock Units granted in 2020 under Issuer's 2018 Incentive Award Plan
  03/14/2023
  1210
  4840.00
  Anirvan Ghosh
  c/o UNITY Biotechnology, Inc.
  285 E. Grand Ave.
  South San Francisco
  CA
  94080
  Restricted Stock Units granted in 2020 under the Issuer's 2020 Incentive Award Plan
  03/31/2023
  1959
  3330.30
  Anirvan Ghosh
  c/o UNITY Biotechnology, Inc.
  285 E. Grand Ave.
  South San Francisco
  CA
  94080
  Restricted Stock Units granted in 2021 under the Issuer's 2018 Incentive Award Plan
  05/01/2023
  1020
  2193.00
  1. Share number reflects post-split units before 1-for-10 reverse stock split as of 10/19/22 2Share number reflects pre-split units before 1-for-10 reverse stock split as of 10/19/22
  05/03/2023
  10/02/2021
  Alexander Nguyen as attorney-in-fact for Anirvan Ghosh pursuant to Power of Attorney