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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Q6f2GhT6KRE8gRsRqLnzgL9wVql4JS2GMflvy/AH5IPuO6sFbTfv5vcdRnf1qhmG
 O6SllpCe/EoZHeOar6f1Hg==

<SEC-DOCUMENT>0000908737-04-000041.txt : 20040122
<SEC-HEADER>0000908737-04-000041.hdr.sgml : 20040122
<ACCEPTANCE-DATETIME>20040122161641
ACCESSION NUMBER:		0000908737-04-000041
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040121
FILED AS OF DATE:		20040122

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SENIOR HOUSING PROPERTIES TRUST
		CENTRAL INDEX KEY:			0001075415
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				043445278
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		400 CENTRE STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02458
		BUSINESS PHONE:		6173323990

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HRPT PROPERTIES TRUST
		CENTRAL INDEX KEY:			0000803649
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15319
		FILM NUMBER:		04537478

	BUSINESS ADDRESS:	
		STREET 1:		400 CENTRE ST
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02458
		BUSINESS PHONE:		6177968350

	MAIL ADDRESS:	
		STREET 1:		400 CENTRE STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02458

	FORMER NAME:	
		FORMER CONFORMED NAME:	HEALTH & RETIREMENT PROPERTIES TRUST
		DATE OF NAME CHANGE:	19940811

	FORMER NAME:	
		FORMER CONFORMED NAME:	HEALTH & REHABILITATION PROPERTIES TRUST
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4_hrptex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<!-- - EDGAR Ease Plus 1.0                                   07/25/03  TT    -->
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
   <periodOfReport>2004-01-21</periodOfReport>
   <notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0001075415</issuerCik>
        <issuerName>SENIOR HOUSING PROPERTIES TRUST</issuerName>
        <issuerTradingSymbol>NYSE: SNH</issuerTradingSymbol>
   </issuer>
   <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000803649</rptOwnerCik>
            <rptOwnerName>HRPT PROPERTIES TRUST</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>400 CENTRE ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEWTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02458</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
         <isDirector>0</isDirector>
         <isOfficer>0</isOfficer>
         <isTenPercentOwner>1</isTenPercentOwner>
         <isOther>0</isOther>
      </reportingOwnerRelationship>
   </reportingOwner>
 <nonDerivativeTable>
   <nonDerivativeTransaction>
      <securityTitle>
         <value>Common Shares of Beneficial Interest</value>
      </securityTitle>
      <transactionDate>
         <value>2004-01-21</value>
      </transactionDate>
      <transactionCoding>
         <transactionFormType>4</transactionFormType>
         <transactionCode>S</transactionCode>
         <equitySwapInvolved>0</equitySwapInvolved>
      </transactionCoding>
      <transactionAmounts>
         <transactionShares>
           <value>3000000</value>
         </transactionShares>
         <transactionPricePerShare>
           <value>18.20</value>
         </transactionPricePerShare>
         <transactionAcquiredDisposedCode>
           <value>D</value>
         </transactionAcquiredDisposedCode>
      </transactionAmounts>
      <postTransactionAmounts>
         <sharesOwnedFollowingTransaction>
           <value>9809238</value>
            <footnoteId id="F1"/>
         </sharesOwnedFollowingTransaction>
      </postTransactionAmounts>
      <ownershipNature>
         <directOrIndirectOwnership>
            <value>D</value>
         </directOrIndirectOwnership>
      </ownershipNature>
   </nonDerivativeTransaction>
 </nonDerivativeTable>
   <footnotes>
      <footnote id="F1"> The Form 4 filed by the Reporting Person for October, 1999 erroneously listed ownership of 12,809,237 shares, rather than 12,809,238.</footnote>
   </footnotes>
   <ownerSignature>
      <signatureName>/s/ Adam Portnoy, Executive Vice President</signatureName>
      <signatureDate>2004-01-22</signatureDate>
   </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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