Nobita and his friends under the waters of the Pacific Ocean. Gian and Suneo take Doraemon's underwater vehicle and travel through the Atlantic Ocean, trying to find a treasure ship.

Nobuyo Oyama
as Doraemon (voice)

Noriko Ohara
as Nobita (voice)

Michiko Nomura
as Shizuka (voice)

Kazuya Tatekabe
as Gian (voice)

Kaneta Kimotsuki
as Suneo (voice)

Michie Kita
as Eru (voice)

Yuji Mitsuya
as Underwater Buggy (voice)

Kosei Tomita
as Poseidon (voice)

Teiji Ōmiya
as Mu Prime Minister (voice)

Masayuki Kato
as Nobita's Father (voice)