Diamond-like carbon (DLC) film was prepared on Co-Cr alloy used for femoral head material of total hip arthroplasty by a hybrid process of plasma-based ion implantation and deposition using hydrocarbon gas. The tension test showed that the adhesive strength of DLC film was increased from 0.4 MPa without ion implantation to 2.8 MPa with carbon ion implantation. Furthermore, implantation of mixed carbon and silicon ions to the substrate led to considerable enhancement of adhesion strength up to 39 MPa that was comparable strength with the epoxy resin glue. DLC coating on Co-Cr alloy reduced the wear loss of ultra high molecular weight polyethylene (UHMWPE) used for a counterpart material in artificial joints. (c) 2005 Published by Elsevier B.V.