Surveys of seamounts in the Southern Indian Ocean were carried out during the 37th and 38th Japanese Antarctic Research Expedition (JARE-37 and JARE-38). Previous uncharted seamounts were identified on board the icebreaker SHIRASE. During the JARE-37 cruise in December 1995,the survey was conducted around (57°S, 98°E) and the shallowest depth of a seamount, 983m, was recorded at 56°59.41′S and 98°05.51′E. The height of the seamount above the ocean floor is more than 3400m and its radius is about 20km. During the JARE-38 cruise in December 1996,the survey was conducted around (60°S, 107°E) and two seamounts were found. The shallowest depth of the northern seamount is 1141m and that of the southern seamount is 2024m. These two seamounts form a small seamount chain about 35km long extending in the northeast-southwest direction.