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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,
 PqQTR/SIl3wtU/RtX+L43bySF8x2xtmQZqFiTZdRHq+OC0iJLQbujItIXmhYL9Vo
 VZFbLE8Sd8QXZb+o0BhgIw==

<SEC-DOCUMENT>0001181018-03-000002.txt : 20030813
<SEC-HEADER>0001181018-03-000002.hdr.sgml : 20030813
<ACCEPTANCE-DATETIME>20030813143357
ACCESSION NUMBER:		0001181018-03-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030813
FILED AS OF DATE:		20030813

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:		03840587

	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>c0001181018d20030813f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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<ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4</documentType><periodOfReport>2003-08-13</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
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Amounts><sharesOwnedFollowingTransaction><value>0</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership><natureOfOwnership><value></value></natureOfOwnership></ownershipNature></derivativeTransaction><derivativeTransaction><securityTitle><value>Stock Option</value></securityTitle><conversionOrExercisePrice><value>37.92</value></conversionOrExercisePrice><transactionDate><value>2003-08-13</value></transactionDate><deemedExecutionDate><value>2003-08-13</value></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>M</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionAmounts><transactionShares><value>1450</value></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><exerciseDate><value>1999-0
3-01</value></exerciseDate><expirationDate><value>2005-08-31</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stock</value></underlyingSecurityTitle><underlyingSecurityShares><value>1450</value></underlyingSecurityShares></underlyingSecurity><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</signatureName><signatureDate>2003-08-13</signatureDate></ownerSignature></ownershipDocument>

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