The experiments of laser cladding nanometer-size WC powder on 2Cr13 stainless steel have been done using 7kW CO2 laser processing system. The microstructure and mechanical characteristic of the WC composite coating were tested by scanning electronic microscope (SEM), X-ray diffraction (XRD), energy dispersion analyzer of X-ray (EDAX) and microhardness tester. The WC composite coating exhibits compact dendritic and reticular interdendritic structure. The XRD data have revealed the phases of coating include Fe, WC, W2C and Fe3C. The nano-WC composite coating has excellent mechanic performances. The surface hardness of composite coating is about 1758HV0.2. Its abrasion proof is 3.5 times as high as that of parent metal.