TiN coatings were successfully prepared by magnetron sputtering technology on biomedical Ti6Al7Nb alloy in order to improve its wear resistance. SEM and XRD were applied to observe the morphologies and analyze the structures of the coating, respectively. Pin-on-disc wear tests were carried out to compare the wear properties of specimen with and without coating. The results show that the coating has a good adhesion to the substrate. The composition and structure of the coating vary with sputtering time. When sputtered for 3 h, the coating is composed of TiN，TiN+Ti2N, Ti2N from the outer surface to the inner layer in sequence. The micro-hardness of TiN layer is increased to 3 times that of substrate. The wear resistance of the surface modified specimens is greatly improved under 10~40 N load, and wear mechanism changes from original oxidative and adhesive to abrasive-dominant