The tribological and mechanical properties of carbon nanofiber (CNF)-filled polytetrafluoroethylene (PTFE) composites with different filler proportions were studied. The worn surfaces of PTFE and carbon nanofiber/PTFE (CNF/PTFE) composites were then examined with scanning electron microscope (SEM). The results show the friction properties of CNF/PTFE composites decreased then increased with the increasing content of CNFs, while the anti-wear properties of CNF/PTFE composites were much higher than that of pure PTFE. The best anti-wear property was obtained with the composite containing 2 wt.% CNFs. The wear volume loss of the composite contained 2 wt.% CNFs was only about 1/700 that of PTFE without CNFs under the condition of 150N and 1.4m/s. Meanwhile, the results also indicate that the mechanical properties of CNF/PTFE composites increased then decreased with the increasing filler concentration, and the composite contained 1 wt.% CNFs has the best mechanical properties. Compare to pure PTFE, the tensile strength and the elongation of CNF/PTFE composites increased about 20% and 70% respectively when the filler content is 1 wt.%. It was seen from the worn surfaces micrographs of PTFE and CNF/PTFE composites that CNFs greatly reduce the adhesive wear of PTFE.