The　in-house　fabricated　quasi-network　Ti5Si3/TiAl　composites　showed　an　excellent　combination　between　light　weight　and　superior　high　temperature　tensile　properties　in　our　previous　work.　However,　the　deformability　was　another　key　factor　which　determined　the　Ti5Si3/TiAl　composites＇　potential　for　high　temperature　applications　in　aeronautics　and　aerospace.　Therefore,　in　this　paper　the　hot　deformation　behaviors　of　the　novel　quasi-network　Ti5Si3/TiAl　composites　at　temperatures　from　900(　degrees)C　to　1200(　degrees)C　with　strain　rates　in　the　range　of　0.001-1　s(-1　)was　systemically　investigated.　The　results　showed　that　the　peak　flow　stress　decreased　with　the　increase　in　the　test　temperature　and　the　decrease　in　the　strain　rate.　The　thermal　compressive　deformation　constitutive　equation　was　built,　and　hence　the　deformation　activation　energy　of　the　quasi-network　Ti5Si3/TiAl　composite　was　confirmed　to　be　564.67　kJ/mol,　slightly　higher　than　or　similar　to　the　TiAl-based　alloys　fabricated　by　traditional　casting　or　powder　metallurgy.　According　to　the　dynamic　material　model　(DMM),　the　hot　processing　maps　with　the　true　strain　of　0.2-0.5　were　established.　It　can　be　concluded　that　the　instability　area　was　mainly　concentrated　in　the　region　of　low　temperature　and　high　strain　rate.　Combined　with　the　microstructural　analysis,　the　optimal　hot　processing　parameters　were　the　temperature　range　of　1125-1200(　degrees)C　and　the　strain　rate　of　0.001-0.01　s(-1),　where　a　large　proportion　of　dynamic　recrystallization　occurred.　It　was　noteworthy　that　the　introduction　of　Ti5Si3　particles　was　conducive　to　accelerating　the　dynamic　recrystallization　and　limiting　the　dynamic　recrystallization　grain　growth.　Besides,　the　distribution　and　size　of　Ti(5)Si(3　)particles　could　be　regulated　by　the　hot　deformation.　Finally,　the　microstructure　evolution　mechanism　in　the　hot　deformation　was　discussed　in　detail,　this　additionally　provided　the　guidance　for　the　practical　plastic　forming.