SiC reinforced aluminum matrix composites (SiCp/Al composites) are typical difficult-to-machine material, and the irregular SiC particles diffused in SiCp/Al composites make the surface quality worse. In this paper, a single-point cutting investigations with finite element simulation were conducted for 65% SiCp/Al composites and aluminum alloy. The surface morphology characteristics of SiCp/Al composites, which mainly include breaking, part breaking, pulling out, protruding, al tearing, and interface debonding, are different from those of aluminum alloy materials. The high-volume SiC particles lower the surface quality and profile dimensional accuracy of SiCp/Al composites. There are thin and discrete layers covered on the machined surface.