The newly developed Co-based alloy containing a certain amount of Ni, Cr, Fe, C, Si, MgO, Y2O3 and nano-Al powders is taken to prepare a ceramic particles, to reinforc Co-based alloy coating on surface of Cu-Cr alloy for crystallizer through pulse laser induced reaction in-situ. The microstructure morphology and coating mechanism is studied experimentally by means of optical micrograph, SEM, and TEM analysis techniques. The results show that under conditions of optimized powder elements and process parameters of the laser-scan (power 50 W, frequency 15 Hz, pulse width 3 ms, scan rate 4.0 mm/s), the coating with a metallurgical interface forms between the Cu alloy substrate and coating is prepared on the surface of Cu-Cr alloy.The structure of Co-Cr-W-C alloy with fine grain and high hardness is formed in the coating, and the ceramic particles in the coating are produced by YAG pulse laser inducing in-situ synthesis, which strengthen the coating. Carbides of W,Cr are precipitated in the coating and that dispersion strengthens the coating. The Co rich area formed in the transition layer of coating leads to the formation of the Cu rich area.