Abstract: The effect s of proton implantation on the t ribological behavior of MoS₂ / PES-C composites werestudied. The st ructural changes of the composites caused by the proton implantation were studied by using inf raredspect ra and X-ray photoelect ron spect roscopy (XPS) . The result s show that part of PES-C degrades af ter protonimplantation , and a carbon- rich st ructure forms on the surface of the composites , whereas there are no obviouschemical changes for MoS₂ during the implantation process. The f riction and wear test s reveal that the wear-resistance of the composites could be improved by proton implantation. Especially when the dose reaches 1. 25 ×10¹⁶ ions/ cm² ,its friction coefficient and wear rate decrease simultaneously. The wear mechanism changes f rom adhesive wear andplastic deformation for the un-implanted composites to fatigue wear for the implanted ones.