Akira Kubo
Taro Kudo
Atsuko Takahashi
Ayako Hoshino
Yukiko Kobayashi
Saki, native girl
Kenji Sahara
Makoto Obata
Yoshio Tsuchiya
Dr. Kyoichi Mida
Tetsu Nakamura
Chieftain Ombo
Yū Fujiki
Asia Development Promotion Division Manager
Noritake Saito
Rico
Yûko Sugihara
Stewardess
Sachio Sakai
The Editor
Chōtarō Tōgin
Yokoyama
Wataru Ōmae
Sakura
Yukihiko Gondō
Sergio Islander
Shigeo Katō
Sergio Islander
Rinsaku Ogata
Sergio Islander
Haruo Nakajima
Gezora / Ganimes / Taro Kudo (water scene stunt double)
Haruyoshi Nakamura
Kamoebas
Ichirô Murakoshi
Space Amoeba / Narrator (voices) (uncredited)
Sōji Ubukata
Airplane Passenger (uncredited)
Yoshio Katsube
News Reporter (uncredited)
Eisaburo Komatsu
News Reporter (uncredited)
Kôichi Satô
News Reporter (uncredited)
Kamayuki Tsubono
Bystander (uncredited)
Seiji Onaka
Sergio Islander (uncredited)
Masaki Shinohara
Sergio Islander (uncredited)