content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <headerData>
  <submissionType>144</submissionType>
  <filerInfo>
  <filer>
  <filerCredentials>
  <cik>0001923461</cik>
  <ccc>XXXXXXXX</ccc>
  </filerCredentials>
  </filer>
  <liveTestFlag>LIVE</liveTestFlag>
  </filerInfo>
  </headerData>
  <formData>
  <issuerInfo>
  <issuerCik>0001888012</issuerCik>
  <issuerName>HilleVax, Inc.</issuerName>
  <secFileNumber>001-41365</secFileNumber>
  <issuerAddress>
  <street1 xmlns="http://www.sec.gov/edgar/common">321 Harrison Avenue</street1>
  <city xmlns="http://www.sec.gov/edgar/common">Boston</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">MA</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">02118</zipCode>
  </issuerAddress>
  <issuerContactPhone>617-213-5054</issuerContactPhone>
  <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Astrid Borkowski</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
  <relationshipsToIssuer>
  <relationshipToIssuer>Officer</relationshipToIssuer>
  </relationshipsToIssuer>
  </issuerInfo>
  <securitiesInformation>
  <securitiesClassTitle>Common Stock</securitiesClassTitle>
  <brokerOrMarketmakerDetails>
  <name>Zurcher Kantonalbank</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">Bahnhofsstrasse  9</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">Postfach</street2>
  <city xmlns="http://www.sec.gov/edgar/common">Zurich</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">V8</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">8010</zipCode>
  </address>
  </brokerOrMarketmakerDetails>
  <noOfUnitsSold>10000</noOfUnitsSold>
  <aggregateMarketValue>155000</aggregateMarketValue>
  <noOfUnitsOutstanding>48437001</noOfUnitsOutstanding>
  <approxSaleDate>12/15/2023</approxSaleDate>
  <securitiesExchangeName>NASDAQ</securitiesExchangeName>
  </securitiesInformation>
  <securitiesToBeSold>
  <securitiesClassTitle>Common Stock</securitiesClassTitle>
  <acquiredDate>03/08/2021</acquiredDate>
  <natureOfAcquisitionTransaction>PURCHASE FROM ISSUER</natureOfAcquisitionTransaction>
  <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
  <isGiftTransaction>N</isGiftTransaction>
  <amountOfSecuritiesAcquired>168100</amountOfSecuritiesAcquired>
  <paymentDate>03/08/2021</paymentDate>
  <natureOfPayment>CASH</natureOfPayment>
  </securitiesToBeSold>
  <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
  <noticeSignature>
  <noticeDate>12/18/2023</noticeDate>
  <signature>Astrid Borkowski</signature>
  </noticeSignature>
  </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 2699}]
text: 144
  0001923461
  XXXXXXXX
  LIVE
  0001888012
  HilleVax, Inc.
  001-41365
  321 Harrison Avenue
  Boston
  MA
  02118
  617-213-5054
  Astrid Borkowski
  Officer
  Common Stock
  Zurcher Kantonalbank
  Bahnhofsstrasse  9
  Postfach
  Zurich
  V8
  8010
  10000
  155000
  48437001
  12/15/2023
  NASDAQ
  Common Stock
  03/08/2021
  PURCHASE FROM ISSUER
  ISSUER
  N
  168100
  03/08/2021
  CASH
  Y
  12/18/2023
  Astrid Borkowski