Specific coatings are frequently used for increasing the life of mechanical parts undergoing severe corrosive and wearing environment. Plasma surfacing has been used to produce high quality coatings with the rapid development of coating technology. In this paper, the dissolution process of WC particles during the plasma surfacing with Fe-based and tungsten carbides composite coatings on AISI 316L stainless steel was studied .The dissolution process of WC particles is investigated by SEM, EDS and phenomenological analysis. Results show that the dissolution of WC particle during the plasma surfacing process is a successive process consisted of dissolution and reaction diffusion. Moreover, the effects of WC dissolved on micro-hardness of coating have been discussed.