To see the general state of the seismic activity in the Kwantô-district, where is noted by the frequent occurrence of earthquakes and especially by the Great Earthquake of Kwantô (Sept. 1, 1923), North Idu (Nov. 26, 1930) and West Saitama (Sept. 21, 1931), the large earthquakes occurred in this district during the last 9 years are investigated about the position of their origins particularly taking account of the depth of focus.