A gradient coating was prepared on a 45 steel substrate to obtain a coating with better wear resistance than the substrate. After the connection layer was prepared on the substrate by laser cladding, the wear-resisting layer was prepared by using iron-based alloy powders without added WC particles and added 3% and 5% WC particles, respectively. The microstructure of the coating was studied by optical microscope (OM), X-ray diffraction (XRD) and scanning electron microscope (SEM). The mechanical properties of coating were studied by Vickers microhardness tester and M-2000 wear tester. The coating is dense without defects such as cracks and pores, and the WC particles inside the coating are clearly visible. The connection layer and the substrate have a good metallurgical bonding. The coating microstructure mainly has equiaxed, columnar and eutectic structure. The phase of the wear layer is austenite (γ-Fe), γ(Fe,Ni) solid solution and Fe-Ni-Cr solid solution. The average microhardness of the coating is 559HV1 which is more than 3 times higher than substrate (182HV1). As the WC content increases, the amount of wear of the coating decreases significantly. The substrate and the connecting layer have planar crystals grown along the surface of the substrate, and the inner structure of the coating is columnar crystal, a dendrite and eutectic structures, and the top of the coating is mostly a small equiaxed crystals. The addition of WC particles did not significantly improve the microhardness of the coating. The wear mechanism of coating without WC is mainly adhesive wear. The coating wear of 3% WC is light wear and wear is still mainly adhesive wear. The wear mechanism of 5% WC wears the lightest wear mechanism is abrasive wear. The addition of WC can significantly improve the wear resistance of the coating.