In this paper, the tribological properties of Si3N4 and Ti/Si3N4 implanted by N ions are studied. The topography of implanting and scratching trace were examined using SEM. By X-ray diffraction for the implanted thin film, the new phase of Ti2N on Ti/Si3N4 layer by N+ implantation was shown. The wear and friction mechanism are also discussed in the paper. Ion beam mixing of interface improves the adhesion between Ti film and Si3N4 substrate.