Cetona is a town and comune in the southern part province of Siena, Tuscany, in an area where Umbria and Lazio meet.

In the first mention of the comune, at the end of the 11th century, Pope Gregory VII granted feudal rights to a member of his family, the Aldobrandeschi.

Grand Duke Cosimo I de' Medici of Tuscany sold Cetona in 1556, to the marchese Chiappino Vitelli (1519–75), who made the fortress into a private residence, and built the piazza below it, today named Piazza Garibaldi.

An early Christian baptistery, now a parish church, mentioned in documents as baptisterium Sancti Johannis de Queneto or de Queteno, may have been named in reference to the Chieteno stream that flows just south of Cetona.

Cetona today is traditionally agricultural (vine, olive), but increasingly basing its economy on agritourism.