<SEC-DOCUMENT>0001127602-11-017164.txt : 20110520
<SEC-HEADER>0001127602-11-017164.hdr.sgml : 20110520
<ACCEPTANCE-DATETIME>20110520170933
ACCESSION NUMBER:		0001127602-11-017164
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110518
FILED AS OF DATE:		20110520
DATE AS OF CHANGE:		20110520

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Harlan Joe E
		CENTRAL INDEX KEY:			0001304956

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-03285
		FILM NUMBER:		11862430

	MAIL ADDRESS:	
		STREET 1:		3M CENTER
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55144

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			3M CO
		CENTRAL INDEX KEY:			0000066740
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				410417775
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3M CENTER
		STREET 2:		BLDG. 220-11W-02
		CITY:			ST PAUL
		STATE:			MN
		ZIP:			55144-1000
		BUSINESS PHONE:		6517332204

	MAIL ADDRESS:	
		STREET 1:		3M CENTER
		STREET 2:		BLDG. 220-11W-02
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55144-1000

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MINNESOTA MINING & MANUFACTURING CO
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
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                <transactionFormType>4</transactionFormType>
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            <ownershipNature>
                <directOrIndirectOwnership>
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                <value>2011-05-18</value>
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                <transactionFormType>4</transactionFormType>
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                <transactionPricePerShare>
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        <nonDerivativeTransaction>
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                <value>Common Stock</value>
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                <transactionFormType>4</transactionFormType>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionPricePerShare>
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        <nonDerivativeTransaction>
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                <value>Common Stock</value>
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                <transactionCode>S</transactionCode>
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            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
                    <value>23043</value>
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        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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                <value>2011-05-18</value>
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                <transactionFormType>4</transactionFormType>
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                    <value>100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>93.72</value>
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                    <value>22943</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
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        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-05-18</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
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            <transactionTimeliness></transactionTimeliness>
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                <transactionShares>
                    <value>100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>93.73</value>
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                <transactionAcquiredDisposedCode>
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                    <value>22843</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
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        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>George Ann Biros, attorney-in-fact for Joe E. Harlan</signatureName>
        <signatureDate>2011-05-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
