Abstract: Cr/GLC monolayer films and Cr/GLC multilayer films with modulation period 6 were prepared by DC magnetron sputtering on 15-5PH steel samples. Scanning electron microscope（SEM）, Raman spectrometer（Raman） were used to analyze the microstructure of the films.The nanoindentation and scratching instruments were used to test their mechanical properties. MFT-5000 multifunctional tribological wear tester was used to test the friction and wear performance of the films in atmosphere and seawater environment, and their wear mechanism was analyzed. The results show that the multilayer structure design improves the density and graphitization degree of the films, and reduces the internal stress. The adhesion force, hardness and elastic modulus of Cr/GLC multilayer films are higher than that of Cr/GLC monolayer films.Under medium and lower loading conditions, the wear forms of the two types of graphite films are mainly abrasive wear, and the tribological properties of Cr/GLC multilayer films are superior to Cr/GLC films in atmospheric and seawater environments.Under higher load, Cr/GLC multilayer films still have better tribological properties than Cr/GLC monolayer films in atmospheric environment, but the wear resistance is degraded in seawater environment.