The fluctuation in the abundance and specie composition of fish was investigated using gape net in Dolsan District of Yeosu Korea from July 2015 to April 2016. A total of 1,331 fishes were sampled and classified into 30 orders, 42 families, and 53 species. The dominant orders are perciformes including 21 famailies and 24 species, followed by scorpaeniformes including 7 families and 13 species, and clueiformes including 6 families and 6 species. Among the 53 fish species collected, Engraulis japonicus was the most frequent specie occupying 43.5%, followed by Argyrosomus argentatus (23.8%), and Leiognathus nuchalis (22.4%). The monthly diversity, evenness, and Richness index were 1.83-2.90, 0.76-0.95 and 3.06-6.40.