Jason
Medea
Acastus
Argos
Zeus
Hermes
Pelias
King Aeetes
Hera
Hylas
Phineas
Phalerus
Hercules
Polydeuces (uncredited)
Castor of Sparta (uncredited)
Dmitrius, Drummer on Argo (uncredited)
Guard in Palace (uncredited)
Lynceus (uncredited)
Medea (voice) (uncredited)
Eupaemus (uncredited)
Briseis (uncredited)
Jason (voice) (uncredited)