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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,
 MRVPtfbLJJ79w/YuK7/fZluGu6YesMxiUfGMvZiz4rjZqfk52J8oxAguNx0dw8zd
 lHiZjgLO6p6IHdI8SXVD6g==

<SEC-DOCUMENT>0000950145-08-000115.txt : 20081104
<SEC-HEADER>0000950145-08-000115.hdr.sgml : 20081104
<ACCEPTANCE-DATETIME>20081104092529
ACCESSION NUMBER:		0000950145-08-000115
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061103
FILED AS OF DATE:		20081104
DATE AS OF CHANGE:		20081104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EMCORE CORP
		CENTRAL INDEX KEY:			0000808326
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				222746503
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			0807

	BUSINESS ADDRESS:	
		STREET 1:		145 BELMONT DRIVE
		CITY:			SOMERSET
		STATE:			NJ
		ZIP:			08873
		BUSINESS PHONE:		7322719090

	MAIL ADDRESS:	
		STREET 1:		145 BELMONT DRIVE
		CITY:			SOMERSET
		STATE:			NJ
		ZIP:			08873

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RUSSELL THOMAS
		CENTRAL INDEX KEY:			0001035930

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22175
		FILM NUMBER:		081159295

	BUSINESS ADDRESS:	
		STREET 1:		C/O JESUP & MERCHANT PARTNERS LLC
		STREET 2:		650 FIFTH AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019
		BUSINESS PHONE:		2123072670
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2006-11-03</periodOfReport>

    <dateOfOriginalSubmission>2006-11-06</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0000808326</issuerCik>
        <issuerName>EMCORE CORP</issuerName>
        <issuerTradingSymbol>EMKR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001035930</rptOwnerCik>
            <rptOwnerName>RUSSELL THOMAS</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>EMCORE CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>10420 RESEARCH ROAD, SE</rptOwnerStreet2>
            <rptOwnerCity>ALBUQUERQUE</rptOwnerCity>
            <rptOwnerState>NM</rptOwnerState>
            <rptOwnerZipCode>87123</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2740978</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On November 6, 2006, the reporting person mistakenly filed a Form 4 reporting the acquisition of 89 shares of common stock that did not in fact occur. As of November 3, 2005, the reporting person owned only 2,740,978 shares of common stock. These shares were erroneously included in the totals on the Forms 4 filed by the reporting person between November 6, 2006 and March 27, 2008.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Thomas J. Russell</signatureName>
        <signatureDate>2008-10-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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