Abstract: To improve unlubricated sliding wear properties of Epoxy, nano-SiC particles were incorporated as fillers to fabricate composites. Effects of surface modification via graft polymerization, content of the nanoparticles and wear conditions were studied. Based on the morphological observation of the worn surfaces and characterization of heat distortion and surface microhardness of the composites, the possible wear mechanism was discussed. The results indicate that the addition of low loading SiC nanoparticles can significantly decrease the specific wear rate and frictional coefficient of Epoxy resin. Much lower wear rate and frictional coefficient of the composites were observed when surface modified nanoparticles were used. The specific wear rate of the composites is 4 times lower than that of unfilled Epoxy and the frictional coefficient is decreased by 36%. It means that the grafting polymer (i.e. polyacrylamide) introduced onto the SiC nanoparticles enhanced the interfacial adhesion, leading to increase crack initiation resistance and improve tribological properties of the composites.