Abstract: Based on w inside-laser coaxial powder feedingM technology the surface of steel 40CrMo (/% : 0. 40C,1. 20Cr, 0. 25Mo) is laser-clad with iron-base alloy powder (/% : 0. 60C, 15. 25Cr, 1. 1 ISi, 1. 85Mo) to increase surface hardness and get idea wear resistance. The hardness HV0 2 value of steel 40CrMo is 250 while the surface hardness HV_0.2 value by laser cladding is 500. It is available to get better metallurgical binding interface between base metal and coating material by base metal pretreated at 200 °C , and the heat affected zone of base metal and binding interface zone are relatively smaller. Due to quick cooling and alloying effect by larger temperature gradient, the hardness of sample bending zone is higher than other area of laser cladding.