Katsuhiko Sasaki
Inventor Goro Ibuki
Yutaka Hayashi
Hiroshi Jinkawa
Hiroyuki Kawase
Rokuro 'Roku-chan' Ibuki
Kanta Mori
Japan Special Defense Forces Chief
Kotaro Tomita
Lead Seatopian Agent
Ulf Otsuki
Seatopian Agent
Sakyo Mikami
Truck Driver's Assistant
Fumiyo Ikeda
Man from Unit 1
Robert Dunham
Emperor Antonio of Seatopia
Gentaro Nakajima
Truck Driver
Ralph Jesser
Antonio's Aide (Radio Operator in White)
Tsugutoshi Komada
Jet Jaguar
Kenpachirō Satsuma
Gigan (as Kengo Nakayama)
Gorō Naya
Emperor Atonio of Seatopia (voice)
Haruo Nakajima
Godzilla (archive footage) (uncredited)
