-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001209191-06-056541.txt : 20061030
<SEC-HEADER>0001209191-06-056541.hdr.sgml : 20061030
<ACCEPTANCE-DATETIME>20061030113508
ACCESSION NUMBER:		0001209191-06-056541
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060930
FILED AS OF DATE:		20061030
DATE AS OF CHANGE:		20061030

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:			GAFFNEY ALAN S
		CENTRAL INDEX KEY:			0001232685

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09965
		FILM NUMBER:		061170975

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		4402480400

	MAIL ADDRESS:	
		STREET 1:		KEITHLEY INSTRUMENTS INC
		STREET 2:		28775 AURORA ROAD
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44139
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>doc5.xml
<DESCRIPTION>FORM 5 SUBMISSION
<TEXT>
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        <issuerName>KEITHLEY INSTRUMENTS INC</issuerName>
        <issuerTradingSymbol>KEI</issuerTradingSymbol>
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            <rptOwnerName>GAFFNEY ALAN S</rptOwnerName>
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            <rptOwnerStreet2>28775 AURORA ROAD</rptOwnerStreet2>
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            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44139</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>VP Comm Mkt &amp; Info Sys</officerTitle>
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    <derivativeTable>
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            <conversionOrExercisePrice>
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            <transactionCoding>
                <transactionFormType></transactionFormType>
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            <exerciseDate>
                <value>2001-07-17</value>
            </exerciseDate>
            <expirationDate>
                <value>2009-07-16</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2000</value>
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                <sharesOwnedFollowingTransaction>
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        <derivativeHolding>
            <securityTitle>
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            <conversionOrExercisePrice>
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                <underlyingSecurityShares>
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            <underlyingSecurity>
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                <value>Performance Award Unit</value>
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            </expirationDate>
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                    <footnoteId id="F5"/>
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    <footnotes>
        <footnote id="F1">Acquired through Employee Stock Purchase and Dividend Reinvestment Plan.</footnote>
        <footnote id="F2">Option became fully vested on February 15, 2005</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 August 10, 2005</footnote>
        <footnote id="F5">Each Performance Award Unit represents the right to receive one common share at the end of the applicable performance period.  The number of units actually earned is subject to adjustment based upon the Company's revenue growth versus that of a defined Peer Group, as well as the Company maintaining an acceptable level of profitability.  Minimum number of units is 0 while the maximum number of units is two times the target number shown.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Mark J. Plush, Attorney-in Fact</signatureName>
        <signatureDate>2006-10-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
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-----END PRIVACY-ENHANCED MESSAGE-----