Character Name : Inventor Goro Ibuki

Original Name : 佐々木勝彦

Gender : Male

Character Name : Hiroshi Jinkawa

Original Name : 林ゆたか

Gender : Male

Character Name : Rokuro 'Roku-chan' Ibuki

Original Name : Hiroyuki Kawase

Gender : Male

Character Name : Japan Special Defense Forces Chief

Original Name : 森幹太

Gender : Male

Character Name : Lead Seatopian Agent

Original Name : 富田浩太郎

Gender : Male

Character Name : Seatopian Agent

Original Name : 大月ウルフ

Gender : Male

Character Name : Truck Driver's Assistant

Original Name : Sakyo Mikami

Gender : Male

Character Name : Man from Unit 1

Original Name : Fumiyo Ikeda

Gender : Male

Character Name : Emperor Antonio of Seatopia

Original Name : Robert Dunham

Gender : Male

Character Name : Truck Driver

Original Name : Gentaro Nakajima

Gender : Male

Character Name : Antonio's Aide (Radio Operator in White)

Original Name : Ralph Jesser

Gender : Male

Character Name : Godzilla

Original Name : Shinji Takagi

Gender : Male

Character Name : Megalon

Original Name : 伊達 秀人

Gender : Male

Character Name : Jet Jaguar

Original Name : 駒田 次利

Gender : Male

Character Name : Jet Jaguar

Original Name : Masachika Mori

Gender : Male

Character Name : Gigan (as Kengo Nakayama)

Original Name : 薩摩剣八郎

Gender : Male

Character Name : Emperor Atonio of Seatopia (voice)

Original Name : 納谷悟朗

Gender : Male

Character Name : Narrator

Original Name : Eisuke Nakanishi

Gender : Male

Character Name : Godzilla (archive footage) (uncredited)

Original Name : 中島春雄

Gender : Male