-----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,
 TAMC77CcAg5uqUDmjobVkN2rGC0pLUE5dcj61dAnJj6rE4SPZR3V3g+WfkHlVmNL
 J8nyXuE5lQghCUWktE23Lg==

<SEC-DOCUMENT>0001127602-10-016216.txt : 20100603
<SEC-HEADER>0001127602-10-016216.hdr.sgml : 20100603
<ACCEPTANCE-DATETIME>20100603103240
ACCESSION NUMBER:		0001127602-10-016216
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100601
FILED AS OF DATE:		20100603
DATE AS OF CHANGE:		20100603

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KEARNEY CHRISTOPHER J
		CENTRAL INDEX KEY:			0001248040

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-04119
		FILM NUMBER:		10874746

	MAIL ADDRESS:	
		STREET 1:		31515 BALLANTYNE CORP
		STREET 2:		C/O SPX CORP
		CITY:			CHARLOTTE
		STATE:			NC
		ZIP:			28277

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NUCOR CORP
		CENTRAL INDEX KEY:			0000073309
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES  ROLLING MILLS (COKE OVENS) [3312]
		IRS NUMBER:				131860817
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2100 REXFORD RD
		CITY:			CHARLOTTE
		STATE:			NC
		ZIP:			28211
		BUSINESS PHONE:		7043667000

	MAIL ADDRESS:	
		STREET 1:		2100 REXFORD ROAD
		CITY:			CHARLOTTE
		STATE:			NC
		ZIP:			28211

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NUCLEAR CORP OF AMERICA INC
		DATE OF NAME CHANGE:	19680911

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AZTEC MECHANICAL CONTRACTORS INC
		DATE OF NAME CHANGE:	19660629
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-06-01</periodOfReport>

    <issuer>
        <issuerCik>0000073309</issuerCik>
        <issuerName>NUCOR CORP</issuerName>
        <issuerTradingSymbol>NUE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001248040</rptOwnerCik>
            <rptOwnerName>KEARNEY CHRISTOPHER J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1915 REXFORD ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHARLOTTE</rptOwnerCity>
            <rptOwnerState>NC</rptOwnerState>
            <rptOwnerZipCode>28211</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-06-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2322</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5599</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The shares of common stock reported are issuable to the reporting person or, if applicable, to his or her estate, as soon as administratively practicable after the termination of the reporting person's service on the board of directors.  The restricted stock units vest immediately upon grant.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kelly J. Wilmoth, attorney-in-fact for Mr. Kearney</signatureName>
        <signatureDate>2010-06-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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