Monteroni d'Arbia is a comune (municipality) in the Province of Siena in the Italian region Tuscany, located about 60 kilometres (37 mi) south of Florence and about 13 kilometres (8 mi) southeast of Siena in the area known as the Crete Senesi.

It takes its names from the Arbia torrent, a tributary of the Ombrone River.

The pieve of Saint John the Baptist, at Corsano, dates from before 1031.

With a nave and two aisles, it is an example of Romanesque architecture with Pisan and Lombard influences.

The church of Saints James and Christopher in Cuna has remains of 14th-century frescoes.