<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-12-31</periodOfReport>

    <issuer>
        <issuerCik>0000006951</issuerCik>
        <issuerName>APPLIED MATERIALS INC /DE</issuerName>
        <issuerTradingSymbol>AMAT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001231878</rptOwnerCik>
            <rptOwnerName>POWELL DENNIS D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O APPLIED MATERIALS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3050 BOWERS AVE, M/S 1268 P.O. BOX 58039</rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>800</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>70247</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents number of restricted stock units automatically acquired based on a value of $61.04 per share, the closing price of Applied Materials, Inc. (&quot;Applied&quot;) common stock on December 31, 2019, in a transaction exempt under Rule 16b-3(d). This automatic acquisition resulted from dividends accrued on vested restricted stock units that, pursuant to Mr. Powell's election to defer, will be converted on a one-for-one basis into shares of Applied common stock and paid to him on the date of his termination of service from the Applied Board of Directors.</footnote>
        <footnote id="F2">Number of shares includes: (a) 58,870 restricted stock units previously reported that have vested and which, pursuant to Mr. Powell's election to defer, will be converted on a one-for-one basis into shares of Applied common stock and paid to him on the date of his termination of service from the Applied Board of Directors, and (b) 5,988 restricted stock units previously reported that will be converted on a one-for-one basis into shares of Applied common stock upon vesting, which vesting is scheduled to occur in March 2020 (subject to continued service as a director through the vesting date).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ To-Anh Nguyen, Attorney-in-Fact</signatureName>
        <signatureDate>2020-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
