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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 FEqtGYaOiDfbi4tRThQMc4xFQEU4QATg5+o6lPm1rGyY7c3pew2g8QKlvrCpAo+H
 AvRdX6jm02oSt6elLT0cag==

<SEC-DOCUMENT>0001246991-09-000084.txt : 20090402
<SEC-HEADER>0001246991-09-000084.hdr.sgml : 20090402
<ACCEPTANCE-DATETIME>20090402154852
ACCESSION NUMBER:		0001246991-09-000084
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090331
FILED AS OF DATE:		20090402
DATE AS OF CHANGE:		20090402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BACOW LAWRENCE S
		CENTRAL INDEX KEY:			0001229890

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13087
		FILM NUMBER:		09727494

	MAIL ADDRESS:	
		STREET 1:		BOSTON PROPERTIES, INC.
		STREET 2:		800 BOYLSTON STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BOSTON PROPERTIES INC
		CENTRAL INDEX KEY:			0001037540
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				042473675
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		800 BOYLSTON STREET
		STREET 2:		SUITE 1900
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
		BUSINESS PHONE:		6172363300

	MAIL ADDRESS:	
		STREET 1:		800 BOYLSTON STREET
		STREET 2:		SUITE 1900
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-03-31</periodOfReport>

    <issuer>
        <issuerCik>0001037540</issuerCik>
        <issuerName>BOSTON PROPERTIES INC</issuerName>
        <issuerTradingSymbol>BXP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001229890</rptOwnerCik>
            <rptOwnerName>BACOW LAWRENCE S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TUFTS UNIVERSITY</rptOwnerStreet1>
            <rptOwnerStreet2>161 PACKARD AVENUE</rptOwnerStreet2>
            <rptOwnerCity>MEDFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02155</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-03-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>570.94</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>35.03</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>570.94</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7859.49</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Phantom Stock Units convert to Common Stock on a 1-for-1 basis.</footnote>
        <footnote id="F2">The Phantom Stock Units are awarded under the Second Amendment and Restatement of the Boston Properties, Inc. 1997 Stock Option and Incentive Plan to non-employee directors who elected to receive Phantom Stock Units in lieu of director cash compensation fees.  The Phantom Stock Units are to be settled in shares of Common Stock (except that fractional units, if any, will be settled in cash) upon the Reporting Person's retirement from the Boston Properties, Inc. Board of Directors.</footnote>
        <footnote id="F3">Includes Phantom Stock Units received pursuant to dividend equivalent rights which were credited to the Reporting Person when and as dividends were paid on Boston Properties, Inc. Common Stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Kelli A. DiLuglio, as Attorney-in-Fact</signatureName>
        <signatureDate>2009-04-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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