Thesmophoriazusae, or Women at the Thesmophoria, is one of eleven surviving comedy plays by Aristophanes. It was first produced in 411 BC, probably at the City Dionysia. The play's focuses include the subversive role of women in a male-dominated society; the vanity of contemporary poets, such as the tragic playwrights Euripides and Agathon; and the shameless, enterprising vulgarity of an ordinary Athenian, as represented in this play by the protagonist, Mnesilochus. The work is also notable for Aristophanes' free adaptation of key structural elements of Old Comedy and for the absence of the anti-populist and anti-war comments that pepper his earlier work. It was produced in the same year as Lysistrata, another play with sexual themes.

Aristophanes was an Ancient Greek comic playwright from Athens and a poet of Old Attic Comedy. He wrote in total forty plays, of which eleven survive virtually complete today. These provide the most valuable examples of a genre of comic drama known as Old Comedy and are used to define it, along with fragments from dozens of lost plays by Aristophanes and his contemporaries.