Based on our insect collecting trip to the Is. Jin-do, Jeollanam-do Province from June 29 to July 1, 2005, a total of 573 lepidopterous species belonging to 37 families are reported, with adding 122 species new to the locality During our survey, the most dominant species was Cryptolechia malacobyrsa Meyrick (Oecophoridae), followed by Sandrabatis crassiella Ragonot (Pyralidae) and Yponomeuta tokyonellus Matsumura(Yponomeutidae), and the family Noctuidae (165 spp.) was the most diverse taxon in species number. We here also discuss the species representing the climatic feature in the island and compare the species diversity with those of other two major islands in Korea, Is. Geoje-do and Is. Jeju-do. Among the species recognized in this study, two species, Epilepia dentata (Matsumura and Shibata) and Meganola costalis (Staudinger) are recorded in Korea for the first time, in spite of the presence of previous notes on the species which is invalid. The adults and genitalia of the two species are illustrated and described briefly.