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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 /CRDCjXhqVEh/yUtmVWkJA==

<SEC-DOCUMENT>0000908737-05-000243.txt : 20050405
<SEC-HEADER>0000908737-05-000243.hdr.sgml : 20050405
<ACCEPTANCE-DATETIME>20050405182521
ACCESSION NUMBER:		0000908737-05-000243
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050404
FILED AS OF DATE:		20050405
DATE AS OF CHANGE:		20050405

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:			PORTNOY BARRY M
		CENTRAL INDEX KEY:			0001241559

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15319
		FILM NUMBER:		05735434

	BUSINESS ADDRESS:	
		STREET 1:		C/O REIT MANAGEMENT RESEARCH LLC
		STREET 2:		400 CENTRE STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02458
		BUSINESS PHONE:		6179281300
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>bportnoyform4_apr0405ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-04-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001075415</issuerCik>
        <issuerName>SENIOR HOUSING PROPERTIES TRUST</issuerName>
        <issuerTradingSymbol>NYSE:SNH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001241559</rptOwnerCik>
            <rptOwnerName>PORTNOY BARRY M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O REIT MANAGEMENT RESEARCH LLC</rptOwnerStreet1>
            <rptOwnerStreet2>400 CENTRE STREET</rptOwnerStreet2>
            <rptOwnerCity>NEWTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02458</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>19509.5</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.61</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>88499.2</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents Mr. Pornoy's proportionate interest in 39,019 common shares of beneficial interest paid by the issuer to Reit
Management &amp; Research LLC (&quot;RMR&quot;), of which Mr. Portnoy is a director and 50% beneficial owner, pursuant to an Advisory
Agreement. Such transfer was exempt from Section 16 of the Securities Exchange Act of 1934, as amended, pursuant to Rule
16a-13 thereunder.</footnote>
        <footnote id="F2">In accordance with the Advisory Agreement referred to above, certain historical share price information was used to determine
the number of common shares of beneficial interest paid to RMR. The per share price amount listed above is the closing sale
price of the issuer's common shares of beneficial interest on the New York Stock Exchange on April 4, 2005.</footnote>
        <footnote id="F3">68,989.7 of such shares are held by Portnoy Family Corporation, a corporation of which Mr. Portnoy is the sole shareholder,
and 19,509.5 of such shares are held by RMR.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Barry M. Portnoy</signatureName>
        <signatureDate>2005-04-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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