Abstract: The friction and wear behavior of diamond carbon like gradient film on Ti6Al4V alloy substrate sliding against ultra high molecular weight polyethylene was investigated under dry sliding and lubrication of Hank's solution and 0.9% NaCl solution, by comparing with that of Ti6Al4V alloy against the same counterpart under the same testing conditions. The worn surfaces of the tested samples were observed with a scanning electron microscope, as an effort to analyze the wear mechanisms. It has been found that the diamond carbon like gradient film has good friction reduction and wear resistant behavior in sliding against the polymer counterpart. Especially, it also registers a lower wear rate of the polymer counterpart as compared with Ti6Al4V alloy. The wear of the diamond carbon like gradient film is characterized by slight abrasive wear which is able to be refrained by the polymer counterpart.