- Ken Utsui
- Super Giant / Starman
- Junko Ikeuchi
- Toshiko / Sister
- Minako Yamada
- (credit only)
- Shôji Nakayama
- Detective Okamoto
- Hiroshi Hayashi
- Chief of Metropolitan Police
- Minoru Takada
- Father
- Utako Mitsuya
- (credit only)
- Chisako Hara
- (as Chisako Tahara)
- Reiko Seto
- Reiko - Okamoto's Sister
- Tomohiko Ãtani
- Vice-Head of Atom AB
- Jôji Ôhara
- Member of Atom AB
- Terumi Hoshi
- (credit only)
- Shinsuke Mikimoto
- Member of Atom AB
- Hiroshi Ayukawa
- Man in Cage
- Ryo Iwashita
- Masao - Boy with Hat
- Noriko Katsuma
- Yoshiko - the Little Girl
- Yukihiko Ãsawa
- Hiroshi - the Kidnapped Boy
