The Izu-Ogasawara Ridge is an island arc along the Izu-Ogasawara Trench where the Pacific Plate subducts beneath the Philippine Sea Plate. Many active volcanic islands and submarine volcanoes exist in a line on the Izu-Ogasawara Ridge, and form a typical volcanic front. Recently, violent submarine volcanic eruption occurred at 24°17.0' N, 141°29.1' E, about 5km north-northeast of the Minami-Io Sima. This area has been called the Hukutoku-Oka-no-Ba, which has records of constructing volcanic island two times. New volcanic island at the Hukutoku-Oka-no-Ba was born in 1986 Jan.20, then vanished in Mar.26. The retrogression and the thermal distribution of this new volcanic island are discussed below.