Abstract Offshore wind turbine generators usually demand higher requirements for key component materials because of the adverse working environment. Therefore, in this study, electromagnetic-assisted laser cladding technology was introduced to prepare the nickel-based composite coating on the Q345R matrix of wind turbine generator key component material. By means of Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Energy Dispersive Spectrometer (EDS), the Vickers hardness tester, friction and wear tester, and electrochemical workstation, the effects of different magnetic field intensities on the macroscopic morphology, microstructure, phase composition, microhardness, wear resistance, and corrosion resistance of the coating were analyzed. The experimental results show that the addition of a magnetic field can effectively reduce the surface defects, improve the surface morphology, and not change the phase composition of the coating. With the increase in magnetic field intensity, the microstructure is gradually refined, and the average microhardness increases gradually, reaching a maximum of 944HV 0.5 at 8 T. The wear resistance gradually increases with the increase in magnetic field intensity, especially when the magnetic field intensity reaches 12 T, the wear rate of the coating is reduced by 81.13%, and the corrosion current density is reduced by 43.7% compared with the coating without a magnetic field. The addition of an electromagnetic field can enhance the wear resistance and corrosion resistance of the nickel-based laser cladding layer. Keywords: laser cladding; steady magnetic field; nickel-based coating; microstructure; wear resistance; corrosion resistance