The surface quality of Cr12MoV die steel in atmospheric medium when it is machined by wire cut electrical discharge machining is higher than that of in liquid medium, but there are also phenomena such as carbonization of machined surface and thermal fatigue damage of electrode wire.In order to solve the above problems,the liquid clad wire supply (double medium) was used to replace the traditional supply method for EDM finishing.The results show that the quality of the surface processed in liquid clad wire supply(double media) is slightly higher than that in atmospheric media and the electrode wire loss is significantly reduced.The research results can provide reference for cutting Cr12MoV die steel with high quality, stability and low loss.