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The engine is the heart of the transport, the level of the domestic enginemanufacturing industry is hampered by the applied materials for the piston which isused for the key components of domestic engine.The hypereutectic Al-Si alloy wasused on piston in foreign country which was dependent on inport in our country.Thepreparing process including the ratio of content,sintering temperature,additive amountwas investigated in this discussion.The modified of Al-Cu-P which was usedhypereutectic Al-Si alloy was prepared by powder metallurgiced. At the same time，the effect of Ni content on the microstructure and mechanical properties wasinvestigated.The optimized prepared process for Al-Cu-P modifier was included as follow: Aland CuP content ratio:1:1; milling time:3h; milling speed:70r/min;load:320KN;packing time:3min; sintering temperature:500℃; and sintering time:1h.The AlP which prelipated from Al-Cu-P modifier could be heterogeneousnucleation which leed to refined rall for primary silicon. The primary silicon can berefined from200μm to about30μm by Al-Cu-P modifier. Compared with the othermodifier, the hardness increased by16.5%, the room temperature strength increasedby32%.the hardness and strength further increased to5%and36%relatively at roomtemperature after heat treatment. The modifier unchanged fracture mechanism whichincluded typical character of intergranular and cleavage fracture.Because of doped Ni element, the precipated Al3Ni was exist, with theimproveing Ni content. The thermal expansion coefficient was decreased, The thermalexpansion coefficient came down to17.80×10-6/℃。The alloy optimum heat treatment process: solution:500℃×3h,water quenching:50℃, the aging procedure:200℃×8h, With the increasing of Ni content, thehardness of the cast alloy gradually increased, the largest tensile strength wasobtained at0.8%, all the alloy hardness reached to138HV, the tensile strength wasincreased with the inproving of Ni content, the optimum content fall into the region of0.8%~1.6%.The friction coefficient increases, the wear resistance is reduce with theincreasing of Ni content in as-cast after adding Ni element. The wear debris is mainly composed of Al, Fe, Si, and a small amount of Fe2O3,and the wear mechanism wasabrasive wear for the alloy.