Objective To investigate the influence of interface of multi-layer films on the film performance. Methods TiN and Ti/ TiN multi-layer films were fabricated on 45# steel by DC magnetron sputtering. The surface morphology and phase composition were analyzed by transmission electron microscopy and X-ray diffraction. The mechanical properties and residual stress of the films were evaluated using nano-indentation tester and electronic film distribution tester. The corrosion resistance properties of TiN and Ti/ Ti multilayer films with different modulation cycles were studied by electrochemical devices. Results The experimental results showed that the surface of the TiN and Ti/ Ti multilayer films was smooth and the structure was dense. The mechanical properties of TiN film were good with small grain and amorphous phase, and there was internal compression residual stress. With decreasing modulation cycle, the elastic modulus and micro-hardness of Ti / TiN multi-layer films first decreased and then increased, the internal residual stress decreased gradually, while the non-uniform degree of distribution increased. The corrosion test of the films in H2 SO4 solution showed: when the modulation cycle of Ti / TiN multilayer film was 1 μm, the corrosion resistance of TiN film was better than that of the multilayer films, with the decrease of modulation cycle of Ti / TiN multilayer films, the corrosion resistance of multilayer films increased gradually; when modulation cycle of Ti / TiN multilayer film was 0. 5 μm, the corrosion resistance of Ti / TiN multilayer film was better than that of TiN film. Conclusion Increased interface was beneficial for decreasing residual stress and enhancing corrosion resistance of multilayer films.