The genus Cosmopterix Hübner is belongs to the subfamily Cosmopteriginae, comprising 11 described species in Korea (Park, 1986; Park, 1994; Sinev and Park, 1994). This genus is major group of the family Cosmopterigidae, with a specific character having the orange postmedian band and silvery-metallic fascia on the forewing. In this study, two species, Cosmopterx argentitegulella Sinev and C. setariella Sinev, are reported for the first time from Korea. Adult and genitalic structure are examined and illustrated. Also, available information, including the distributional ranges, collecting localities and host plants are provided. Consequently 13 species have been recorded in Korea until now.