Abstract: The friction and wear behavior of polyethersulfone (PES) composites reinforced with various carbon fibers was investigated on a pin on disc test rig under dry sliding against AISI1045 steel disc. The effect of solid lubricants including polytetrafluoroethylene (PTFE) and graphite on the friction and wear behavior of the composites was examined on the same test rig as well. It has been found that the wear of the composites is reduced considerably by incorporation of carbon fibers, while long carbon fiber is superior to short one in improving the friction and wear behavior of the PES composites. A low specific wear rate of the composite is obtained at a volume fraction of carbon fiber about 15%. It is further decreased by incorporation of the solid lubricants PTFE and graphite. Based on the examination of the wear mechanisms and the comparison of the calculated and experimental friction coefficients and specific wear rates of the composites, it has been demonstrated that the friction and wear behavior of the PES composites can be explained with Friedrich Voss wear model and Friedrich Lu friction model.