(in order of appearance)
| Orestes: | son of Agamemnon and Clytemnestra, he’s been living away from Argos since he was a young boy |
| Pylades: | Orestes’ best friend and constant companion |
| Electra: | Orestes’ older sister, who has been living unhappily in her mother’s house since Agamemnon died |
| The Libation Bearers: | a chorus of women who have been enslaved in war, and who with Electra bring liquid offerings (libations) to Agamemnon’s grave |
| A Servant: | who keeps the door of the palace |
| Clytemnestra: | queen of Argos, who killed her husband Agamemnon, in part to avenge the killing of their daughter Iphigeneia |
| Kilissa: | old nurse of Orestes |
| Aegisthus: | lover of Clytemnestra, who has ruled with her in Argos since the death of his cousin Agamemnon |