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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 E/dtifJRFB6+HGWbXHOCMRoMQC02gApN+T63AxK+91K5bgibVR1FzYmIBpOb7Zac
 hpj8332maj7WxaS7nUIFoA==

<SEC-DOCUMENT>0001181018-03-000003.txt : 20031103
<SEC-HEADER>0001181018-03-000003.hdr.sgml : 20031103
<ACCEPTANCE-DATETIME>20031103105446
ACCESSION NUMBER:		0001181018-03-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031031
FILED AS OF DATE:		20031103

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PARRISH D MICHAEL
		CENTRAL INDEX KEY:			0001181018

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-04119
		FILM NUMBER:		03971730

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

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>c0001181018d20031103f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4</documentType><periodOfReport>2003-10-31</periodOfReport><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000073309</issuerCik><issuerName>NUCOR CORP</issuerName>        <issuerTradingSymbol>NUE</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001181018</rptOwnerCik><rptOwnerName>PARRISH D MICHAEL</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>2100 REXFORD ROAD</rptOwnerStreet1><rptOwnerStreet2></rptOwnerStreet2><rptOwnerCity>CHARLOTTE</rptOwnerCity><rptOwnerState>NC</rptOwnerState><rptOwnerZipCode>28211-</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>0</isDirector><isOfficer>1</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther><officerTitle>EXECUTIVE VICE PRESIDENT</officerTitle><otherText></otherText></reportingOwnerRelationship></reportingOwner><nonDeriv
ativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-10-31</value></transactionDate><deemedExecutionDate><value>2003-10-31</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>5999</value></transactionShares><transactionPricePerShare><value>41.67</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>25012</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction
><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-10-31</value></transactionDate><deemedExecutionDate><value>2003-10-31</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>S</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>5999</value></transactionShares><transactionPricePerShare><value>54.78</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>19013</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></nonDerivativeTransaction></nonDeri
vativeTable><derivativeTable><derivativeTransaction><securityTitle><value>Stock Option</value></securityTitle><conversionOrExercisePrice><value>41.67</value></conversionOrExercisePrice><transactionDate><value>2003-10-31</value></transactionDate><deemedExecutionDate><value>2003-10-31</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>5999</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>2003-03-01</value></exerciseDate><expirationDate><value>2010-02-28</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>5999</value></underlyingSecurityShares></underlyingSecu
rity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes></footnotes><ownerSignature><signatureName>Kelly J. Wilmoth - Attorney-in-fact</signatureName><signatureDate>2003-11-03</signatureDate></ownerSignature></ownershipDocument>

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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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