A　10　vol%　TiB2/Al-Zn-Mg-Cu-Zr　composite　was　prepared　by　Melt-SHS　techniques.　The　microstructures　and　mechanical　properties　of　the　composite　were　analyzed　in　this　work.　The　results　show　that　TiB2　particles　with　an　average　particle　size　of　0.67　mu　m　are　dispersed　in　the　composite　uniformly　well　combined　with　the　matrix　alloy　after　hot　extrusion　and　T6　treatment.　The　addition　of　TiB2　particles　resulted　in　a　grain　size　reduction　by　64.4%.　The　hardness,　UTS,　TYS　and　elastic　modulus　of　the　composite　are　increased　by　9%,　20.2%,　22.3%　and　24.6%,　respectively.　However,　the　elongation　is　reduced　with　the　addition　of　TiB2　particles.　The　improvement　of　yield　strength　is　attributed　to　the　uniform　dispersion　of　the　fine　TiB2　particles　in　the　alloy　matrix　and　the　major　contribution　is　from　the　dislocation　strengthening　mechanism,　which　has　an　additional　contribution　of　13.8%.　In　addition,　the　Orowan　strengthening　mechanism,　grain　refinement　and　load　bearing　strengthening　mechanism　have　also　contributed.