The work aims to study influence of different Mo contents on hardness, binding force and corrosion resistance of CrN films. CrMoN films were deposited with different amounts of Mo atom on the surface of 4Cr13 stainless steel by multi-arc ion plating (MAIP). The hardness, binding force, electrochemical corrosion resistance and element content of CrMoN films were respectively investigated by microhardness tester, adhesion scratch tester, electrochemical measuring instrument and energy disperse spectroscopy. The results showed that when the Mo atomicity fractions of CrMoN achieved 0.15%, 4.23%, 5.15%, 7.09%, 14.26%, 21.12% and 31.08%, the hardness values were respectively 2141.1HV, 2416.0HV, 2416.0HV, 2962.3HV, 2580.4HV, 2710.5HV and 2441.8HV while the binding forces were respectively 45, 47, 52, 57, 38, 37, 34 N. In 3.5% NaCl solution, the relative corrosion rate was respectively 6.53, 4.12, 1, 2.22, 8.72, 2.42 and 2.44 times of that Mo (5.15%). In 1 mol/L NaOH solution, the relative corrosion rate was respectively 6.74, 5.29, 1.49, 2.82, 2.57, 1, 7.25 times of that of Mo (14.26%). In 1 mol/L H2SO4 solution, the relative corrosion rate was respectively 9.20, 4.10, 10.31, 9.25, 1, 3.29 and 7.46 times of that of Mo (14.26%). The binding force can be up to 57 N and microhardness reaches the maximum—2962.3HV when the Mo atomicity fraction reaches 7.09%. Corrosion resistance is best in H2SO4 solution and NaOH solution when the Mo atomicity fraction reaches 14.26%. Corrosion resistance is best in NaCl solution when the Mo atomicity fraction reaches 5.15%. Corrosion mechanism of composite films is mainly pitting corrosion, and crevice and galvanic corrosion are present as well.