Abstract: The biocompatibility and surface characteristics of dental materials surfacemodified by an amorphous diamond film were investigated. The dental materials are poly(methyl methacrylate) (PMMA) and pure titanium and the amorphous diamond film surface was produced by a plasma assisted cathode arc discharge under vacuum. The biocompatibility was evaluated by cell cultivation and animal implants and the wearability of the PMMA tooth after modification was analyzed by a scratching test. The surface characteristics of the film were characterized by SEM. The corrosion resistance of the surface of pure titanium dental material after the surface modification was investigated by the electrochemical analysis of a simulated oral cavity filled with artificial saliva. Results show that the toxicity of the amorphous diamond film modified dental materials is zero, and the hemolysis ratio is 3.08%. After polarization pretreatment, the PMMA artificial tooth coated with an amorphous diamond film has a maximium adhesion force of 10.86±0.79N. The selfcorrosive potential and the overpassivation potential of the pure titanium after the surface modification were increased. These results demonstrate that coating the surface of dental materials with a diamond film meets the requirements of biocompatibility, anticorrosion and adhesion strength.