-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 HBm/5p2doYcUhN6rL+K0lcJmrEPwFXxOyf6VfJznduw8n497QfwWajzaQCRWZhie
 BTDJKd+cOXKdj5bMXGv3DA==

<SEC-DOCUMENT>0001179110-06-003616.txt : 20060214
<SEC-HEADER>0001179110-06-003616.hdr.sgml : 20060214
<ACCEPTANCE-DATETIME>20060214121320
ACCESSION NUMBER:		0001179110-06-003616
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060213
FILED AS OF DATE:		20060214
DATE AS OF CHANGE:		20060214

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PETRI FREDRICK W
		CENTRAL INDEX KEY:			0001235749

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14469
		FILM NUMBER:		06609879

	MAIL ADDRESS:	
		STREET 1:		1825 S GRANT STREET
		STREET 2:		SUITE 630
		CITY:			SAN MATEO
		STATE:			CA
		ZIP:			94402

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SIMON PROPERTY GROUP INC /DE/
		CENTRAL INDEX KEY:			0001063761
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				046268599
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		115 WEST WASHINGTON STREET
		STREET 2:		SUITE 1200 E
		CITY:			INDIANAPOLIS
		STATE:			IN
		ZIP:			46204
		BUSINESS PHONE:		3176361600

	MAIL ADDRESS:	
		STREET 1:		115 WEST WASHINGTON STREET
		STREET 2:		SUITE 1200 E
		CITY:			INDIANAPOLIS
		STATE:			IN
		ZIP:			46204

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CORPORATE PROPERTY INVESTORS INC
		DATE OF NAME CHANGE:	19980610
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-02-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001063761</issuerCik>
        <issuerName>SIMON PROPERTY GROUP INC /DE/</issuerName>
        <issuerTradingSymbol>SPG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001235749</rptOwnerCik>
            <rptOwnerName>PETRI FREDRICK W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1825 S. GRANT STREET, STE. 630</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN MATEO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94402</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-02-13</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>300</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>80.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40460</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Fredrick W. Petri, and his attorney-in-fact, Shelly Doran</signatureName>
        <signatureDate>2006-02-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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