Abstract: Al₂O_3f+C_f/ZL109 short fibers reinforced hybrid composites were fabricated by squeeze casting.The effects of alumina and carbon fibres volume fraction on the drilling machinability of the hybrid composites were researched.The influences of quantity used in cutting and orientation of fiber on drilling force,tool wear and drilling precision were investigated,and the mechanism was analyzed. The conclusion can be drawn that according to the drill wear,the machinability of Al₂O_3f+C_f/ZL109 is inferior to that of ZL109 alloy.