Based on the compositional and structural designing of Co-based cladding materials, a nano-particle reinforced Co-based alloy gradient coating is produced by laser-inducing in-situ technique on the crysrallizer Cu alloy. The microstructure, hardness, anti-wear property and mechanism of the gradient coating are studied using analysis techniques. The results show that the gradient coating is composed of three layers, which are the surface, inside structure and a metallurgical bond between the gradient coating and Cu alloy substrate. Nano-particles of Cr-Ni-Fe-C, MoNi4, Cr7C2, and WC1-x synthesized in-situ play role as a reinforced Co-base gradient coating. The number of the ceramic particles increases from the first layer to the third layer. The micro-hardness of the gradient coating increases gradually from 94 HV of the substrate to 523 HV of the outmost layer. The graphite has function of improving frictional property of the gradient coating.