In order to investigate moth diversity in the bordering islands and inland in the southwest area of Korean Peninsula, a total of 1,127 individuals of 270 species from 214 genera, 16 families, 1 order were collected from four inland sites and four island sites near Mokpo, at the southern end of the Korean Peninsula from April to October of 2009. According to the analysis of the collected moths, Noctuidae with its 102 species were the most frequently collected order and followed by Geometridae and Pyralidae. Among the 5 regions studied every month (Yangeulsan (Mt.), Oedaldo, Yudalsan (Mt.), Ibamsan (Mt.), Seungdalsan (Mt.)), Mt. Seungdalsan showed the highest species diversity with 129 species from 452 moths collected, followed by decreasing order of Yangeulsan at 70 species from 139 moths, Ibamsan at 59 species from 116 moths, Oedaldo at 58 species from 133 moths and Yudalsan of 48 species from 125 moths. In the three regions in which samples were taken once, Dalido showed the highest figure at 49 species from 98 moths collected, followed by Gohado at 23 species from 37 moths and Heosado at 14 species from 27 moths.