In order to improve the interfacial bonding between carbon fiber and epoxy resin,so as to improve the tribological properties of the composites,polydopamine and polyethylenimine were used to modify the carbon fiber.The chemical composition and microstructure of carbon fiber surface before and after modification were analyzed by infrared spectrum analyzer and scanning electron microscope.The mechanical and tribological properties of the composites was tested by universal testing machine and friction and wear testing machine.The results show that the surface roughness and active functional groups increase of the carbon fiber after surface treatment,which improves the interfacial adhesion between carbon fiber and resin,and improves the bending strength and tensile strength of the composite.Compared with the epoxy resin composites reinforced by unmodified carbon fiber,the wear resistance of epoxy resin composites reinforced by surface modified carbon fiber is greatly improved,and the wear mechanism of composites changes from fatigue wear to abrasive wear.