Abstract: Three groups of TiO2 nanotube layers with different inner diameters were fabricated on titanium substrate by anodization. Morphology, microhardness, nanohardness and roughness of specimen surfaces were analyzed by a scanning electron microscope, hardness instrument and surface roughometer. The fretting wear tests of specimens against a UHMWPE ball were carried out in air on a PLINT fretting fatigue machine using the ball / plane contact under four normal loads respectively. Results suggested that coefficients of friction decreased as normal load increased for the same frictional pair. The TiO2 nanotube layers reduced the coefficients between Ti specimen and UHMWPE. Under different normal load, the coefficients increased as the nanotube diameter increased. The friction coefficients of nanotube specimens were lower than that of the contrast. In sliding against UHMWPE, TiO2 nanotube layers had good of load-bearing, anti-stripping and wear-resistant properties. The wear mechanism of the frictional pair involved abrasive wear and material loss on surface layer resulted from UHMWPE plastic deformation.