<SEC-DOCUMENT>0001562180-20-000661.txt : 20200129
<SEC-HEADER>0001562180-20-000661.hdr.sgml : 20200129
<ACCEPTANCE-DATETIME>20200129121202
ACCESSION NUMBER:		0001562180-20-000661
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200127
FILED AS OF DATE:		20200129
DATE AS OF CHANGE:		20200129

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Thompson Steven M.
		CENTRAL INDEX KEY:			0001793595

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10816
		FILM NUMBER:		20557192

	MAIL ADDRESS:	
		STREET 1:		250 EAST KILBOURN AVENUE
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53202

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MGIC INVESTMENT CORP
		CENTRAL INDEX KEY:			0000876437
		STANDARD INDUSTRIAL CLASSIFICATION:	SURETY INSURANCE [6351]
		IRS NUMBER:				391486475
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		250 EAST KILBOURN AVENUE
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53202
		BUSINESS PHONE:		4143476480

	MAIL ADDRESS:	
		STREET 1:		250 EAST KILBOURN AVENUE
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53202
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primarydocument.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-01-27</periodOfReport>

    <notSubjectToSection16>false</notSubjectToSection16>

    <issuer>
        <issuerCik>0000876437</issuerCik>
        <issuerName>MGIC INVESTMENT CORP</issuerName>
        <issuerTradingSymbol>MTG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001793595</rptOwnerCik>
            <rptOwnerName>Thompson Steven M.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>250 EAST KILBOURN AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>EVP&amp;CRO-Mort Gty Ins Corp</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>CommonStock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-01-27</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <footnoteId id="F1"/>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>108000.00</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>149121.00</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These represent restricted stock units (&quot;RSUs&quot;) that will vest on February 28, 2023 to the extent, if any, the performance goal to which they are subject is met.  If it is not possible to determine whether the performance goal has been met on such vesting date, the vesting date generally shall be extended until such determination can be made.  Any of these RSUs that have not vested on April 15, 2023 shall be forfeited.</footnote>
        <footnote id="F2">These RSUs were awarded to the reporting person pursuant to the Issuer's 2015 Omnibus Incentive Plan and no price was paid by the reporting person for them.</footnote>
    </footnotes>

    <remarks>This Form 4 is being signed by the reporting person's attorney-in-fact pursuant to a previously filed power of attorney.</remarks>

    <ownerSignature>
        <signatureName>Martha F. Tsuchihashi, Attorney-in-Fact</signatureName>
        <signatureDate>2020-01-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
