Objective To in-situ synthesize WC-B₄C reinforced Ni-based composite coating on the surface of steel Q235 substrate using laser cladding technique. Methods Using WO₃, B₂O₃, C and Ni60 as pre-coating raw materials, in-situ WC-B₄C reinforced Ni-based composite coating was synthesized by laser cladding technology. The microstructure observation, component and phases analysis of the coatings were performed to analyze the friction and wear resistance performance. Results The results indicated that a good finish WC-B₄C particulate reinforced composite coating could be achieved by proper laser cladding processes. The coatings epitaxial growing from the substrate with excellent bonding between the coating and substrate was assured by the strong metallurgical interface. The in situ synthesized WC-B₄C particulate reinforced Ni-based composite coating had very high hardness of 1200HV0. 3, and excellent wear resistance which was only 1 / 3 that of pure Ni60 coatings. Conclusion The coating layer had improved hardness and wear resistance, which was due to the in-situ synthesis of WC-B₄C and its homogenous distribution in the cladding layer.