Laser cladding of 316L steel powders on 45 Steel Substrate was conducted, and microstructure of laser cladding coating was analyzed. The microhardness of laser cladding layer was examined. The results showed that microstructure of laser cladding zone was exiguous dentrite, and there were dispersion of hard spots in the laser cladding zone. Performances of eroderesistant, surface hardness and wearresistant were improved obviously. The residual stress in cladding coating was usually tensile stress, with the further increasing depth of coating, the residual stress began to fall and stabilized gradually, and the residual stress values in substrate was smaller than in cladding coating.