Abstract: TiN films were deposited on NiTi shape memory alloys by an arc ion plating technique. The phase structure, surface characteristics, the thickness, the hardness and the linking stress of TiN film were characterized by X-ray diffractionmeter, scanning electron microscopy, atom force microscopy, profilometer, and nano-indenter, successively. The friction and wear characteristics of NiTi alloys with and without TiN film were investigated under the same testing conditions on a tribometer. The results showed that TiN film was compact and even improved the hardness of NiTi alloy. The film presented good friction-reducing and anti-wear properties under dry friction, lubrication of Hank's solution and 0.9% NaCl solution, respectively. It indicated that the friction and wear characteristics of NiTi alloy can be improved by TiN film.