Ultra-high molecular weight polyethylene composites reinforced with carbon fibers (CF) and polytetrafluoroethylene (PTFE) were prepared. The effects of fillers on the microstructure and fretting wear behavior of composites were investigated. The results of X-ray diffraction and scanning electron microscopy measurements indicated that the microstructure of composites were greatly changed, and the distinct interface between fillers and matrix had been formed with the incorporation of CF and PTFE. In addition, results also showed that the simultaneously filled with CF and PTFE at a proper weight fraction contributed to dramatically improving the friction reducing and wear resistance of ultra-high molecular weight polyethylene. It can be found that there exists synergism between fillers. Copyright (c) 2015 John Wiley & Sons, Ltd.