Nick Adams as Astronaut F. Glenn

Akira Takarada as Astronaut K. Fuji

Keiko Sawai as Haruno Fuji

Kumi Mizuno as Miss Namikawa

Jun Tazaki as Dr. Sakurai

Akira Kubo as Tetsuo Teri

Yoshio Tsuchiya as Controller of Planet X

Takamaru Sasaki as Chairman of Earth Committee

Gen Shimizu as Minister of Defense

Kenzō Tabu as Commander from Planet X

Yoshifumi Tajima as General

Haruo Nakajima as Godzilla

Masaki Shinohara as Rodan

Shōichi Hirose as King Ghidorah

Gorō Naya as Astronaut F. Glenn (voice)

Toki Shiozawa as Tetsuo's Mother

Nadao Kirino as Military Aide

Kôji Uno as Namikawa's Associate

Tōru Ibuki as Xian

Kazuo Suzuki as Xian

Fuyuki Murakami as Councilman

Noriko Sengoku as Female Delegate

Someshō Matsumoto as Buddhist Priest

Kamayuki Tsubono as Councilman

Yasuhisa Tsutsumi as Official

Rinsaku Ogata as Scientist

Masaaki Tachibana as Scientist

Yutaka Oka as Reporter

Saburô Iketani as News Reader

Yoshizo Tatake as Xian

Mitsuo Tsuda as Xian

Ryôji Shimizu as Xian

Minoru Itō as Xian

Takuzō Kumagai as Xian

Tadashi Okabe as Reporter

Hideki Furukawa as Xian