-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 F4Da8B/Hz2gOd//nxSlw3DeElmWqjn7RYk2kEmMXMFvY3OmbCZ5DGrsr8veFAuhS
 Aa7qPGR6+YAc5D5yxllgFg==

<SEC-DOCUMENT>0001187864-06-000022.txt : 20060504
<SEC-HEADER>0001187864-06-000022.hdr.sgml : 20060504
<ACCEPTANCE-DATETIME>20060504165304
ACCESSION NUMBER:		0001187864-06-000022
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060503
FILED AS OF DATE:		20060504
DATE AS OF CHANGE:		20060504

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TRIBUNE CO
		CENTRAL INDEX KEY:			0000726513
		STANDARD INDUSTRIAL CLASSIFICATION:	NEWSPAPERS:  PUBLISHING OR PUBLISHING & PRINTING [2711]
		IRS NUMBER:				361880355
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1225

	BUSINESS ADDRESS:	
		STREET 1:		435 N MICHIGAN AVE
		STREET 2:		STE 600
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611
		BUSINESS PHONE:		3122229100

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MORRISON ROBERT S
		CENTRAL INDEX KEY:			0001025098

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08572
		FILM NUMBER:		06809168

	BUSINESS ADDRESS:	
		STREET 1:		THREE LAKES CR
		CITY:			NORTHFIELD
		STATE:			IL
		ZIP:			60093
		BUSINESS PHONE:		2128782087

	MAIL ADDRESS:	
		STREET 2:		120 PARK AVE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>f4forrsm.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-05-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000726513</issuerCik>
        <issuerName>TRIBUNE CO</issuerName>
        <issuerTradingSymbol>TRB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001025098</rptOwnerCik>
            <rptOwnerName>MORRISON ROBERT S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2>600 EAST WESTMINSTER ROAD</rptOwnerStreet2>
            <rptOwnerCity>LAKE FOREST</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60045</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>2006-05-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2642.71</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>28.38</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12939.89</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <ownerSignature>
        <signatureName>/s/ Mark W. Hianik, attorney-in-fact</signatureName>
        <signatureDate>2006-05-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----