The Korean nudibranch faunal study has been conducted since 2011 and five species including Dermatobranchus otome Baba, 1992, Mexichromis festiva (Angas, 1864), Noumea nivalis Baba, 1937, Hoplodoris armata (Baba, 1993), and Okenia hiroi (Baba, 1938) were newly reported with re-descriptions and figures. Also, Noumea purpurea Baba, 1949 was re-described with illustrations because previous records for this species were given without a description. Two congeneric species in the genus Noumea could be distinguished by ground color, dorsal markings, color of the mantle edge and gills, and mantle and dorsal marking. In addition, mitochondrial cytochrome c oxidase subunit I (COI) sequences of five species were provided for further molecular identification study. Consequently, a total of 43 species have been reported for the Korean nudibranch fauna.