(in order of appearance)
| Dionysus: | the god of wine and drama |
| Xanthias: | his long-suffering slave |
| Heracles: | the divine strong man, half-brother of Dionysus |
| A Corpse: | at his funeral |
| Charon: | the boatman to the Underworld |
| Chorus of Frogs: | competitive singers who live in the lake |
| A Priest: | who leads the Initiates |
| Chorus of Initiates: | initiates of the Mysteries (followers of secret cults of Iacchus and Demeter) |
| Doorman: | serving at the house of Pluto |
| Landlady: | aggrieved Underworld innkeeper |
| Plathane: | another aggrieved Underworld innkeeper |
| Euripides: | the great, recently-deceased tragedian |
| Aeschylus: | the great, long-dead tragedian |
| Pluto: | the god of the Underworld |
| …and more: | attendants and guards and so on… |