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

    <schemaVersion>X0609</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2026-05-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0002090441</issuerCik>
        <issuerName>Iron Dome Acquisition I Corp.</issuerName>
        <issuerTradingSymbol>IDACU</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001775072</rptOwnerCik>
            <rptOwnerName>Norden Matthew J.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O IRON DOME ACQUISITION I CORP.</rptOwnerStreet1>
            <rptOwnerStreet2>244 FIFTH AVENUE, SUITE #1814</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10001</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>See Remarks</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002090440</rptOwnerCik>
            <rptOwnerName>Iron Dome Acquisition I Parent LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O IRON DOME ACQUISITION I CORP.</rptOwnerStreet1>
            <rptOwnerStreet2>244 FIFTH AVENUE, SUITE #1814</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10001</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Warrant</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>11.5</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-05-18</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2750000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Ordinary Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2750000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2750000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Simultaneously with the consummation of the Company's initial public offering, Iron Dome Acquisition I Parent LLC (the &quot;Sponsor&quot;) acquired, at a price of $1.00 per warrant, 2,750,000 warrants (the &quot;Private Placement Warrants&quot;) in a private placement for an aggregate purchase price of $2,750,000. Each Private Placement Warrant entitles the holder thereof to purchase one Class A ordinary share at $11.50 per share, subject to adjustment.</footnote>
        <footnote id="F2">The Sponsor is the record holder of the shares reported herein. Mr. Norden, the issuer's Chief Financial Officer and director, is the sole member of Iron Dome Acquisition I Manager LLC, the managing member of the Sponsor, and makes all investment and voting decisions with respect to the securities held the Sponsor. As such, Mr. Norden may be deemed to have or share beneficial ownership of the securities held directly by the Sponsor. Mr. Norden disclaims any beneficial ownership of the reported securities other than to the extent of any pecuniary interests Mr. Norden may have therein, directly or indirectly.</footnote>
        <footnote id="F3">The Private Placement Warrants will become exercisable at any time commencing 30 days after the completion of the Company's initial business combination.</footnote>
        <footnote id="F4">The Private Placement Warrants will expire five years after the completion of the Company's initial business combination, at 5:00 p.m., New York City time, or earlier upon redemption or liquidation.</footnote>
    </footnotes>

    <remarks>1. Chief Financial Officer and sole member of Iron Dome Acquisition I Manager LLC, the managing member of Iron Dome Acquisition I Parent LLC.</remarks>

    <ownerSignature>
        <signatureName>/s/ Matthew J. Norden</signatureName>
        <signatureDate>2026-05-18</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Matthew J. Norden, as the sole member of the Managing Member of Iron Dome Acquisition I Parent LLC</signatureName>
        <signatureDate>2026-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
