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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,
 La8kDGR//xieXK6/92ho4slcUAikAArSUqnf2X4+1BrYU6oIvvff+wmIjH1CGNWP
 wNvxK6JS25ysbe14ZMpBYg==

<SEC-DOCUMENT>0000916076-06-000113.txt : 20060419
<SEC-HEADER>0000916076-06-000113.hdr.sgml : 20060419
<ACCEPTANCE-DATETIME>20060419113439
ACCESSION NUMBER:		0000916076-06-000113
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060417
FILED AS OF DATE:		20060419
DATE AS OF CHANGE:		20060419

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARTIN MARIETTA MATERIALS INC
		CENTRAL INDEX KEY:			0000916076
		STANDARD INDUSTRIAL CLASSIFICATION:	MINING, QUARRYING OF NONMETALLIC MINERALS (NO FUELS) [1400]
		IRS NUMBER:				561848578
		STATE OF INCORPORATION:			NC
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2710 WYCLIFF RD
		CITY:			RALEIGH
		STATE:			NC
		ZIP:			27607
		BUSINESS PHONE:		9197814550

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STEWART JONATHAN T
		CENTRAL INDEX KEY:			0001084495
		STANDARD INDUSTRIAL CLASSIFICATION:	MINING, QUARRYING OF NONMETALLIC MINERALS (NO FUELS) [1400]
		STATE OF INCORPORATION:			NC
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12744
		FILM NUMBER:		06766365

	BUSINESS ADDRESS:	
		STREET 1:		2710 WYCLIFF RD
		CITY:			RALEIGH
		STATE:			NC
		ZIP:			27607
		BUSINESS PHONE:		9197814550

	MAIL ADDRESS:	
		STREET 1:		MARTIN MARIETTA MATERIALS INC
		STREET 2:		2710 WYCLIFF ROAD
		CITY:			RALEIGH
		STATE:			NC
		ZIP:			27607
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-17</periodOfReport>

    <issuer>
        <issuerCik>0000916076</issuerCik>
        <issuerName>MARTIN MARIETTA MATERIALS INC</issuerName>
        <issuerTradingSymbol>MLM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001084495</rptOwnerCik>
            <rptOwnerName>STEWART JONATHAN T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MARTIN MARIETTA MATERIALS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2710 WYCLIFF ROAD</rptOwnerStreet2>
            <rptOwnerCity>RALEIGH</rptOwnerCity>
            <rptOwnerState>NC</rptOwnerState>
            <rptOwnerZipCode>27607</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP Human Resources</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-04-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value>E</value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>36834</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Jonathan T. Stewart</signatureName>
        <signatureDate>2006-04-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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