This paper presents an experimental investigation of milling silicon carbide particulate reinforced aluminum(SiCp/Al) metal matrix composites workpiece with the assistance of ultrasonic vibrating along the spindle direction. Cuttingforce and the surface quality characterized by surface roughness and surface morphology are discussed by comparingconventional milling with ultrasonic vibration milling at different spindle speeds. The experimental results show thatultrasonic vibration milling can lower the cutting force, reduce the surface roughness, improve surface smoothness and alsoeliminate processing stripes.