<p>Due to the high reflectivity of copper alloy to infrared laser, it is extremely difficult to prepare coatings on copper alloy by infrared laser cladding technology. Based on the high absorption rate of copper alloy to blue laser beam, CoCrFeNi coating was prepared on copper alloy by infrared-blue composite laser cladding technology in this paper, and the forming quality of the coating and the evolution of molten pool under different laser beams and different laser powers were investigated. Optical microscope (OM), VHX-1000 ultra-depth-of-field three-dimensional microscope and energy-dispersive X-ray spectrometer were used to observe the macroscopic morphology of the cladding layer surface, and the real-time evolution process and splash phenomenon of the molten pool were observed with an ultra-high-speed camera. The results show that the coating prepared by the infrared-blue composite laser beam forms a dense metallurgical bond with the copper alloy substrate. Additionally, splashing around the molten pool is significantly reduced, and the molten pool is more stable compared with infrared laser cladding coating, which is the main reason for the excellent quality of the coating. The infrared-blue composite laser beam can obtain sufficient energy density at a low power output on copper alloy, effectively reducing defects such as cracks and porosity in the coating and improving the forming quality of the coating. This study is expected to provide references and ideas for high-quality preparation coatings on copper alloy surfaces.</p>