Thin film coatings of (Cao.6Mg0.4)Zr4(P04)6 (CMZP) and Mg stabilized AhTiOs ( Mg-Ah Ti05 ) on dense SiC substrates were investigated using sol-gel coating techniques. The thickness and quality of both CMZP and Mg-Ah Ti05 coatings were found to depend on the solution concentration and lift rate. Double coatings were applied to obtain homogeneous and crack-free coatings. The quality of double coatings was influenced by different first and second coating thickness. The CMZP coated samples were fired in controlled atmospheres to have the pure CMZP phase. Unhydrolyzed solution of Mg-AhTiOs was utilized instead of hydrolyzed solution to improve the quality of Mg-AhTiOs coatings. Aging process was found to improve the quality of CMZP and Mg-Ah TiOs coatings. SiC samples coated with CMZP and Mg-Ah TiOs exhibited good thermal shock resistance and greatly improved the high temperature alkali corrosion resistance.