Castiglione Chiavarese (Ligurian: O Castiggion [u kastiˈdʒuŋ]) is a comune (municipality) in the Metropolitan City of Genoa in the Italian region Liguria, located about 50 kilometres (31 mi) southeast of Genoa.

Castiglione Chiavarese borders the following municipalities: Carro, Casarza Ligure, Deiva Marina, Maissana, Moneglia.

In ancient times the area of Castiglione probably marked the border between the Ligurian and the Etruscan cultures.

The Val Petronio was colonized by Benedictine monks after the fall of the Western Roman Empire; later it became a possession of the Fieschi family who, in 1276, sold Castiglione to the Republic of Genoa.

Castiglione Chiavarese is located across the SS523 State Road connecting it to Sestri Levante, which also houses the nearest railway station.