Raymond Burr

Steve Martin

Toyoaki Suzuki

Shinkichi (as Tuyoaki Suzuki)

Frank Iwanaga

Security Officer Tomo Iwanaga (as Frank Iwaiga)

Akira Takarada

Ogata (as Akiro Takarata)

Akihiko Hirata

Dr. Serizawa

Sachio Sakai

Hagiwara

Takashi Shimura

Dr. Yamane

Momoko Kôchi

Emiko Yamane (as Momaku Kuchi)

Fuyuki Murakami

Dr. Tabata (uncredited)

Ren Yamamoto

Seiji (uncredited)

Mikel Conrad

George Lawrence (uncredited)

Toranosuke Ogawa

President of Company (uncredited)

Tadashi Okabe

Dr. Tabata's Assistant (uncredited)

Kokuten Kōdō

The Old Fisherman (uncredited)

Kenji Sahara

Man on Boat (uncredited)

Haruo Nakajima

Godzilla (uncredited)

Katsumi Tezuka

Godzilla (uncredited)

Raymond Royer

Unidentified Character (voice)

Michel François

Unidentified Character (voice)

Roland Ménard

Unidentified Character (voice)

Violette Jean

Unidentified Character (voice)

René Blancard

Unidentified Character (voice)

Maurice Favières

Unidentified Character (voice)

Dominique Rémy

Unidentified Character (voice)

Gérard Kérise

Unidentified Character (voice)

Louis Perdoux

Unidentified Character (voice)

Claude Dupuis

Unidentified Character (voice)

Eddy Rasimi

Unidentified Character (voice)

Yasuhisa Tsutsumi

Odo Islander (uncredited)

Kenzo Echigo

Sailor playing harmonica on Eiko Maru (uncredited)

Masaki Shinohara

Eiko Maru crewmember (uncredited)

Yū Fujiki

Eiko Maru wireless communications officer (uncredited)

Tokio Ôkawa

Male family member of missing sailors (uncredited)

Ishirō Honda

Substation worker (uncredited)

Shōichi Hirose

Representative (uncredited)

Haruya Sakamoto

Newspaper reporter on Shikine (uncredited)

Kōji Uruki

Assistant to announcer on Shikine (uncredited)