-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001209191-10-052098.txt : 20101029
<SEC-HEADER>0001209191-10-052098.hdr.sgml : 20101029
<ACCEPTANCE-DATETIME>20101029124425
ACCESSION NUMBER:		0001209191-10-052098
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101027
FILED AS OF DATE:		20101029
DATE AS OF CHANGE:		20101029

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KEITHLEY INSTRUMENTS INC
		CENTRAL INDEX KEY:			0000054991
		STANDARD INDUSTRIAL CLASSIFICATION:	INSTRUMENTS FOR MEAS & TESTING OF ELECTRICITY & ELEC SIGNALS [3825]
		IRS NUMBER:				340794417
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		28775 AURORA RD
		CITY:			SOLON
		STATE:			OH
		ZIP:			44139
		BUSINESS PHONE:		2162480400

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PENDERGRASS LARRY L
		CENTRAL INDEX KEY:			0001234664

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09965
		FILM NUMBER:		101150694
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
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        <issuerName>KEITHLEY INSTRUMENTS INC</issuerName>
        <issuerTradingSymbol>KEI</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>PENDERGRASS LARRY L</rptOwnerName>
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            <rptOwnerStreet2>28775 AURORA ROAD</rptOwnerStreet2>
            <rptOwnerCity>SOLON</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44139</rptOwnerZipCode>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP New Product Development</officerTitle>
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                <underlyingSecurityShares>
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            <underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
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                <value>2019-12-04</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                </underlyingSecurityShares>
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                    <value>13200</value>
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                <value>0.00</value>
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                <footnoteId id="F6"/>
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            <expirationDate>
                <footnoteId id="F6"/>
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                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                    <footnoteId id="F6"/>
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                <sharesOwnedFollowingTransaction>
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                    <footnoteId id="F6"/>
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                <directOrIndirectOwnership>
                    <value>D</value>
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        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Unit Award</value>
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                <value>0.00</value>
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                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4400</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Performance Award Unit represented the right to receive one common share.  The number of units initially awarded was a target (as shown in Table II), and the actual number of units that vested and converted to shares (which could range from 0 shares to twice the target number of shares) was based upon: a) the Company's revenue growth as compared to a defined Peer Group and, b) the Company maintaining an acceptable level of profitability during the performance period which ended on September 30, 2010.  Based on the Company's performance, the units converted into a number of shares equal to the target number.</footnote>
        <footnote id="F2">Shares issuable upon vesting of Performance Award Units were withheld to settle associated tax liabilities.</footnote>
        <footnote id="F3">Date reported applies to 50% of total, one-half of the balance is then exercisable in each succeeding year.</footnote>
        <footnote id="F4">Option became fully vested on February 15, 2005</footnote>
        <footnote id="F5">Restricted unit awards will become fully vested on February 6, 2013.  Common shares represented by such vested restricted unit awards will be delivered promptly after such vesting date.</footnote>
        <footnote id="F6">Each Performance Award Unit represents a right to receive one common share.  The number of units comprising the initial award are adjusted (ranging from a maximum of twice the number of units comprising the initial award, to a minimum of no units), based on award program metrics that compare the Company's total shareholder return performance occurring during the Measurement Period to comparable total shareholder return performance reported by companies in the Russell Microcap Index.  Awarded units earned based on these metrics as of September 30, 2012 (the vesting date) are converted to shares under the Plan and will be issued on or before December 31, 2012.</footnote>
        <footnote id="F7">Restricted unit awards will become fully vested on December 4, 2013.  Common Shares represented by such vested restricted unit awards will be delivered promptly after such vesting date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Mark J. Plush, Attorney-in Fact</signatureName>
        <signatureDate>2010-10-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----