PURPOSE: To produce an Al alloy piston provided with a head having high heat resistance and strength by disposing a preform of SiC whiskers in the bottom of the casting cavity of a metallic mold for casting and casting a molten Al alloy dispersed with the SiC whiskers into the cavity from above the perform at the time of casting the Al alloy piston.

CONSTITUTION: The disk-shaped preform 3 of the SiC whiskers is disposed in the bottom in the casting cavity 2 of the casting mold 1 at the time of casting the Al alloy piston for an internal combustion engine. The melt 4 of the Al alloy dispersed and incorporated therein with 0.05W0.2vol.% SiC whiskers is poured into the cavity from above the preform and is pressurized and molded under 100W1000kgf/cm2 pressure by an upper punch 5 for pressure molding. The casting is removed from the mold after solidification. The Al alloy piston, the head part of which has the excellent heat resistance and strength and the skirt part has the excellent wear resistance, is thus produced.