Abstract: The high vanadium high speed steel and high chromium cast iron compound roll was producted by the equipment of electromagnetic hemicontinuous compound casting and 45 steel had been used as axes material in the experiment.The structure and property of interfaces about high vanadium high speed steel and high chromium cast iron rolls had been studied.The result indicates that,the compound contact surface element of high vanadium high speed steel and high chromium cast iron compound roll diffuses obviously to each other.The structure morphology of diffusion layer is in the transient state.The thickness of diffusion layer is the basal same,about 50 μm.The microhardness of diffusion layer is between wear layer and axis,and it changes gently in the interface.Comparing to high chromium cast,The microhardness of high vanadium high speed steel is somewhat low.The shearing toughness and the impact toughness is somewhat high.But both of them have a little difference could meet with operating requirement.