Abstract: Friction and wear properties of nano-TiO_2 filled polyurethane coatings with polyfluo-150 wax are investigated,and a comparison of tribological performance is made between nano-TiO_2 filled the polyurethane with polyfluo-wax coatings and micro-TiO_2 filled polyurethane coatings polyfluo-wax on MHK-500 friction and wear tester in sliding against stainless steel ring under dry friction condition.The worn surface and transfer films of PU coatings with polyfluo-wax filled nano-TiO_2 and micro-TiO_2 were examined with SEM and optical micrograph.As a result,polyurethane coating with polyfluo-wax filled nano-TiO_2 and micro-TiO_2 exhibited much high friction coefficient than polyurethane coating with polyfluo-wax did.5% nano-TiO_2 could greatly reduce wear of polyurethane coating with polyfluo-wax,and its wear life is longer than that of micro-TiO_2 filled the polyurethane coating with polyfluo-wax.Friction and wear behavior of the coating filled 5% nano-TiO_2 depends on the applied load and sliding speed.