with conservative values in the Bigeummyeon of Sinan gun. Of the total 93 uninhabited islands in the Bigeummyeon, 8 islands, Jageundaeseom, Maeseom, Sowoosedo, Dongudo, Woosedo, Biamokseom, Chilbaldo and Nodaeseom are known as conservative ones, which take up about 10% of the total islands. Natural environments of uninhabited islands are generally divided into a morphological constituent of geology and geomorphology and a biological one of fauna and flora. In particular, geology and geomorphology play important roles as a ecological bases in which many organisms can live, and both are essential elements in understanding the landscapes of the above islands. Therefore, these uninhabited islands with excellent geological and geomorphological features must be preserved, and their importance need be emphasized.