Mochizuki was born on Ōsakikamijima, an island in the Seto Inland Sea, now part of Hiroshima Prefecture, where his father was an entrepreneur and ship owner.
Shinichi Mochizuki | Keisuke Minami | Keisuke Kuwata | Keisuke Itagaki | Yūko Mochizuki | Otori Keisuke | ''Mochizuki'' (bottom) and seaplane tender Japanese seaplane tender Kiyokawa Maru | ''Mochizuki'' | Mochizuki |