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            <filer>
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                    <ccc>XXXXXXXX</ccc>
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            <liveTestFlag>LIVE</liveTestFlag>



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        <issuerInfo>
            <issuerCik>0001069258</issuerCik>
            <issuerName>KRATOS DEFENSE &amp; SECURITY SOLUTIONS INC.</issuerName>
            <secFileNumber>001-34460</secFileNumber>
            <issuerAddress>
                <ns2:street1>1 Chisholm Trail, Suite 300</ns2:street1>
                <ns2:city>Round Rock</ns2:city>
                <ns2:stateOrCountry>TX</ns2:stateOrCountry>
                <ns2:zipCode>78681</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(512) 238-9840</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>MARIE C MENDOZA</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>E*TRADE FINANCIAL CORPORATION</name>
                <address>
                    <ns2:street1>3 EDISON DRIVE</ns2:street1>
                    <ns2:city>ALPHARETTA</ns2:city>
                    <ns2:stateOrCountry>GA</ns2:stateOrCountry>
                    <ns2:zipCode>30005</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>1000</noOfUnitsSold>
            <aggregateMarketValue>14000.00</aggregateMarketValue>
            <noOfUnitsOutstanding>127603137</noOfUnitsOutstanding>
            <approxSaleDate>07/20/2023</approxSaleDate>
            <securitiesExchangeName>NASD</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>01/04/2022</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1000</amountOfSecuritiesAcquired>
            <paymentDate>01/04/2022</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>MARIE C MENDOZA</name>
                <address>
                    <ns2:street1>1 Chisholm Trail, Suite 300</ns2:street1>
                    <ns2:city>Round Rock</ns2:city>
                    <ns2:stateOrCountry>TX</ns2:stateOrCountry>
                    <ns2:zipCode>78681</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/16/2023</saleDate>
            <amountOfSecuritiesSold>1000</amountOfSecuritiesSold>
            <grossProceeds>14000.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>MARIE C MENDOZA</name>
                <address>
                    <ns2:street1>1 Chisholm Trail, Suite 300</ns2:street1>
                    <ns2:city>Round Rock</ns2:city>
                    <ns2:stateOrCountry>TX</ns2:stateOrCountry>
                    <ns2:zipCode>78681</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>05/17/2023</saleDate>
            <amountOfSecuritiesSold>1447</amountOfSecuritiesSold>
            <grossProceeds>20258.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>MARIE C MENDOZA</name>
                <address>
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                    <ns2:stateOrCountry>TX</ns2:stateOrCountry>
                    <ns2:zipCode>78681</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>05/04/2023</saleDate>
            <amountOfSecuritiesSold>7211</amountOfSecuritiesSold>
            <grossProceeds>100954.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>07/20/2023</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>09/12/2022</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Marie C Mendoza</signature>
        </noticeSignature>
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144
0001660112
XXXXXXXX
LIVE
0001069258
KRATOS DEFENSE & SECURITY SOLUTIONS INC.
001-34460
1 Chisholm Trail, Suite 300
Round Rock
TX
78681
(512) 238-9840
MARIE C MENDOZA
Officer
Common
E*TRADE FINANCIAL CORPORATION
3 EDISON DRIVE
ALPHARETTA
GA
30005
1000
14000.00
127603137
07/20/2023
NASD
COMMON
01/04/2022
Restricted Stock
ISSUER
N
1000
01/04/2022
Not Applicable
N
MARIE C MENDOZA
1 Chisholm Trail, Suite 300
Round Rock
TX
78681
Common
06/16/2023
1000
14000.00
MARIE C MENDOZA
1 Chisholm Trail, Suite 300
Round Rock
TX
78681
Common
05/17/2023
1447
20258.00
MARIE C MENDOZA
1 Chisholm Trail, Suite 300
Round Rock
TX
78681
Common
05/04/2023
7211
100954.00
07/20/2023
09/12/2022
/s/ Marie C Mendoza