| Cleisthenes | |
| Native Name: | Κλεισθένης |
| Native Name Lang: | grc |
| Nationality: | Athenian |
| Occupation: | Theoros (delegate) |
| Known For: | Role during the Peloponnesian War |
| Notable Works: | Mentioned in Aristophanes' plays (The Frogs, The Clouds, Lysistrata, Thesmophoriazusae) |
| Era: | Classical Greece |
Cleisthenes (; grc|Κλεισθένης), also Clisthenes or Kleisthenes, was a prominent Athenian delegate (theoros) during the Peloponnesian War (431 BC). The comedian Aristophanes used him frequently as the butt of jokes and as a character in his plays, ridiculing him for being effeminate and/or homosexual. He is notably mentioned in The Frogs, The Clouds, Lysistrata, and Thesmophoriazusae.