In this paper, fiber laser was used to clad Ni60 coating and Ni60+WC composite coating on the surface of high strength and toughness steel. The morphology of cladding layer under different process parameters was studied, and the influence of reinforcement phase on the microstructure of the cladding layer was investigated. Meanwhile the microstructure and hardness of the cladding layer before and after cryogenic were analyzed. The results show that the laser process parameters affect the microstructure of the cladding layer and no needle-like eutectic structure appears in the cladding layer of Ni60 with high laser power. After adding WC powder into Ni60 powder, grain refinement appears in the microstructure. For the Ni60 cladding layer with low hardness, cryogenic treatment results in precipitation of more carbides and thus high hardness. While cryogenic treatment contributes to refinement of microstructure and enhanced hardness of the Ni60+WC cladding layer with low hardness.