Cobalt based tungsten carbide composite material [WC-Co] is industrial applied for coating on tip of cutting tools and molds due to its high hardness and wear resistance. However, it is difficult to coat composite materials while maintaining the properties of the powder because of the different melting points of the metals. Thus, we pay attention to a Laser metal deposition (LMD) method. The LMD is one of additive manufacturing technologies in which the material powder is fed, and laser irradiated simultaneously at the processing point to melt and solidify the material powder to form layers, which can add new functions to material surface of any shape. However, conventional LMD has some problems to heat the powder ununiformly in flight, which a molten pool is required on the substrate to weld with powder and substrate, it was caused significantly thermal distortion and dilution. Thus, we have developed a multi-beam LMD system with two high intensity 200W blue diode lasers. The multi beam LMD can heat uniformly the powder in flight resulting in lower thermal distortion and dilution. Especially, using a blue laser with a shorter wavelength than the IR laser used in conventional LMD can improve the light absorption rate for WC-Co power and the steel substrate, to save an energy compared with the conventional LMD. In this study, we try to form a WC-Co coating on a steel substrate surface using the multi-beam LMD system equipped with two blue diode lasers.