Abstract: Plasma chromizing was achieved on Q235 steel and 45 steel surface and formed high chrome layer.Then plasma carburizing was proceed on alloyed high chromium layer.The results show the surface chromium composition content is more than 40% and the chromium elements are infinity dissolved into α-Fe.The chromium composition of alloyed layer distribute flat and grads.The carbonization of alloyed layer is secondly carbides from solid.The carbides are dispersion,thin,uniformity.The surface carbon content is morn than 2.8%.There is no ledeburite on alloyed layer.The surface hardness in alloyed layer is 1 800 HV after quenching and tempering.The wear resistant is 7 times than GCr15 steel.