In next-generation aircraft engines, it is assumed that the operating temperature will exceed the present critical temperature of any conventional metallic materials(more than 1400℃) . Therefore, the application of SiC/SiC ceramic matrix composite(CMC) as the main material is expected. SiC forms a protective silica scale when expose to an oxidative environment thus providing extra protection from problems caused by oxidation. However, the protective silica scale may pose a problem due to its reaction with the water vapor during the combustion to create gaseous silicon hydroxides that usually reduce its thickness. This problem retards the practical realization of CMC engines for aircrafts. Consequently, additional environmental barrier coatings(EBC) are necessary to protect the CMC components from any oxidative degradation, thus, ensuring the reliability of CMC engines. In this study, a new deposition process, the suspension plasma spray(SPS) that produces much denser coatings by feeding numerous single micron fine particles as the suspension was proposed and considered due to its applicability to form the EBC. And with respect to the SPS, it was clarified that the coating structure and composition were largely influenced by the residence time of the suspensions in the plasma flame, and subsequently, optimum spray conditions were examined.