ゴジラ対メガロ

佐々木勝彦

Inventor Goro Ibuki

林ゆたか

Hiroshi Jinkawa

Hiroyuki Kawase

Rokuro 'Roku-chan' Ibuki

森幹太

Japan Special Defense Forces Chief

富田浩太郎

Lead Seatopian Agent

大月ウルフ

Seatopian Agent

三上左京

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)

Shinji Takagi

Godzilla

伊達 秀人

Megalon

駒田 次利

Jet Jaguar

森正親

Jet Jaguar

薩摩剣八郎

Gigan

納谷悟朗

Emperor Atonio of Seatopia (voice)

中西英介

Narrator

中島春雄

Godzilla (archive footage) (uncredited)

Kôetsu Ômiya

Anguirus (archive footage) (uncredited)