Abstract:CrMoN coatings were deposited with different Mo content on 4Cr13 stainless steel by multi-arc ion plating (MAIP). The binding force, hardness and corrosion resistance properties of CrMoN coatings were respectively investigated by adhesion scratch tester, hardness instrument, and electrochemical measuring instrument. The corrosion solution concentration were in 3.5% NaCl solution, 1 mol?L-1 NaOH solution and 1 mol?L-1 H2SO4 solution. Influence of different Mo content on corrosion resitance of CrMoN coatings was investigated. The result indicate that: NaCl-type fcc-phased (Cr, Mo)N were observed; when the Mo content achieved to 31.08%, diffraction peak of Mo2N was observed in the direction of (200), the coatings are always composed of three phases CrN, (Cr,Mo)N and Mo2N. When the Mo content achieve to 7.09%, the biggest binding force and micro-hardness are respectively 57 N, 2962.3 HV; When the Mo content achieve to 14.26%, the corrosion resistance of CrMoN coatings is the best in 1 mol?L-1 NaOH solution and 1 mol?L-1 H2SO4 solution; When the Mo content achieve to 5.15%, the corrosion resistance of CrMoN coatings is the best in 3.5% NaCl solution; Corrosion mechanism of coatings is mainly pitting corrosion, and crevice and galvanic corrosion occue.