Yōsuke Natsuki as Detective Shindo

Yuriko Hoshi as Naoko Shindo

Hiroshi Koizumi as Professor Murai

Takashi Shimura as Dr. Tsukamoto

Emi Ito as Shobijin

Yumi Ito as Shobijin

Akiko Wakabayashi as Princess Maas Doulina Salno of Selgina

Hisaya Itō as Chief Assassin Malmess

Akihiko Hirata as Chief Detective Okita

Minoru Takada as Prime Minister (uncredited)

Someshō Matsumoto as Alien Expert (uncredited)

Ikio Sawamura as Honest Fisherman (uncredited)

Kōzō Nomura as Geologist (uncredited)

Kenji Sahara as Editor in Chief Kanamaki

Susumu Kurobe as Assassin with Mustache (uncredited)

Tōru Ibuki as Short-Tie Assassin (uncredited)

Kazuo Suzuki as Door-Opener Assassin (uncredited)

Haruya Katō as Journalist (uncredited)

Shin Ōtomo as Boss of Assassins (uncredited)

Senkichi Ōmura as Would-Be Hat Retriever (uncredited)

Yutaka Nakayama as Tourist with Lost Hat (uncredited)

Heihachirō Ōkawa as Astronomer (uncredited)

Hideyo Amamoto as Princess Salno's aide (uncredited)

Yoshio Kosugi as Chief of Infant Island (uncredited)

Yoshibumi Tajima as Ship Captain (uncredited)

Yutaka Oka as Meteoritic (uncredited)

Kôji Uno as Hotel Clerk (uncredited)

Shigeki Ishida as Man in Crowd (uncredited)

Toshihiko Furuta as Villager (uncredited)

Kotaro Tomita as Villager (uncredited)

Ichiya Aozora as Self / TV Host (uncredited)

Senya Aozora as Self / TV Host (uncredited)

Yuriko Hanabusa as Mother Shindo (uncredited)

Hideo Shibuya as Journalist (uncredited)

Haruo Nakajima as Godzilla (uncredited)

Shōichi Hirose as King Ghidorah (uncredited)

Masaki Shinohara as Rodan (uncredited)

Kōji Uruki as Rodan (uncredited)