More than 264 species were observed at 12 research stations of Chuuk and Quop atoll. Total 317 species were recorded in Cuukish waters involved Moen atoll, Nomwin atoll and Kuop atoll. In this data, unvisual small fishes living in sand bottom and coral polyps were excepted. 222 fish species were observed in Chuuk atoll, 108 species in Namwin and 181 species in Kuop atoll (Table 2). In some station of Chuuk lagoon, we found destroyed marine ecosystem by using explosive for fisheries. Those stations showed low fish species diversity.