Abstract: Cr12MoV steel was subjected to electropulse-assisted nitride infiltration treatment, and the thickness and properties of nitriding layer were characterized and analyzed. The results show that the thickness of nitriding layer on the surface of Cr12MoV steel increases obviously after electric pulse assisted nitriding treatment.For the pulse voltage is 900 V, the thickness of nitriding layer increases with the pulse frequency.When the pulse frequency is 12 Hz, the nitride layer thickness of the Cr12MoV steel increases from 60 μm when no electric pulse treated is applied to 210 μm, is 3.5 times than that of the routine nitriding treatment sample.