-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 QVSLwpnqKvUtox2LzxwBQPSfrVc6zN8qjh+o/2ph5gOeuYdzcLc3u8ZpkdcM8P2r
 q84a4I089aioDBBh5kycSQ==

<SEC-DOCUMENT>0001246991-11-000024.txt : 20110131
<SEC-HEADER>0001246991-11-000024.hdr.sgml : 20110131
<ACCEPTANCE-DATETIME>20110131155619
ACCESSION NUMBER:		0001246991-11-000024
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110127
FILED AS OF DATE:		20110131
DATE AS OF CHANGE:		20110131

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LUSTIG MATTHEW J
		CENTRAL INDEX KEY:			0001203367

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13087
		FILM NUMBER:		11559486

	MAIL ADDRESS:	
		STREET 1:		LAZARD FRERES REAL ESTATE INVESTORS LLC
		STREET 2:		30 ROCKEFELLER PLZA 50TH FL
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10020

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>2011-01-27</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001203367</rptOwnerCik>
            <rptOwnerName>LUSTIG MATTHEW J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LAZARD</rptOwnerStreet1>
            <rptOwnerStreet2>30 ROCKEFELLER PLAZA</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10020</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>LTIP Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2011-01-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>302</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common OP Units</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>302</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>302</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents units of limited partnership interest in Boston Properties Limited Partnership (BPLP), of which the Issuer is the general partner, issued as long term incetive compensation pursant to the Issuer's equity based compensatory programs.  Conditioned upon minimum allocations to the capital accounts of the LTIP Units for federal income tax purposes, each LTIP Unit may be converted, at the election of the holder, into a common unit of limited partnership interest in BPLP (Common Unit).  Each Common Unit acquired upon conversion of an LTIP Unit may be redeemed, at the election of the holder, for cash equal to the then fair market value of a share of the Issuer's Common Stock, except that the Issuer may, at its election as directed by BPLP, acquire a Common Unit presented for redemption for one share of Common Stock.</footnote>
        <footnote id="F2">The LTIP Units will vest on the date of the Issuer's 2011 annual meeting of stockholders.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Kelli A. DiLuglio, as Attorney-in-Fact</signatureName>
        <signatureDate>2011-01-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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