In this paper, SiC nanoparticles reinforced AM60 alloys were fabricated by semisolid process with pretreatment of SiC nanoparticles. The microstructure, hardness and mechanical properties of the alloys have been investigated. The X-ray photoelectron spectroscopy (XPS) was also used for analyzing elements chemical status of the nanoparticles and the alloys. The microstructure, hardness and mechanical properties of SiC nanoparticles reinforced magnesium alloys are better than those of AM60 alloys without SiC nanoparticles addition. The results show that semisolid process was suitable for fabricating SiC nanoparticles reinforced magnesium alloys.