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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-01-01</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001721736</rptOwnerCik>
            <rptOwnerName>Ghanayem Steve G.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O APPLIED MATERIALS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3050 BOWERS AVE., M/S 1268, PO BOX 58039</rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>SVP, New Mrkts &amp; Alliances Grp</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-01-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4029</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>51.12</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>477858</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4379.519</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k) Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents number of shares that were automatically withheld upon vesting of restricted stock units to cover tax withholding obligations in a transaction exempt under Rule 16b-3.</footnote>
        <footnote id="F2">Number of shares includes 286,803 performance shares and restricted stock units previously reported that in the future will be converted on a one-for-one basis into shares of Applied Materials common stock upon vesting, which vesting is scheduled to occur as follows: (a) 20,000 restricted stock units are scheduled to vest in October 2018, (b) 88,746 performance shares are scheduled to vest in installments in December of 2018 and 2019, (c) 51,911 performance shares are scheduled to vest in December 2019, which number of shares is the target amount, and the actual number of shares that may vest ranges from 0% to 200% of the target amount, depending on achievement of specified performance goals, (d) 34,608 restricted stock units are scheduled to vest in installments in December of 2018 and 2019, (e) 63,522 restricted stock units are scheduled to vest in installments in December of 2018 through 2021, depending on achievement of a specified performance goal, and (f) 28,016 performance shares are scheduled to vest in December 2020, which number of shares is the target amount, and the actual number of shares that may vest ranges from 0% to 200% of the target amount, depending on achievement of specified performance goals (all vesting is subject to continued employment through each applicable vest date).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Harpreet S. Bal, Attorney-in-Fact</signatureName>
        <signatureDate>2018-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
