Peralillo is a Chilean town and commune in Colchagua Province, O'Higgins Region.
According to the 2002 census of the National Statistics Institute, Peralillo spans an area of 282.6 km (109 sq mi) and has 9,729 inhabitants (5,007 men and 4,722 women). Of these, 5,882 (60.5%) lived in urban areas and 3,847 (39.5%) in rural areas. The population grew by 6.4% (585 persons) between the 1992 and 2002 censuses.
As a commune, Peralillo is a third-level administrative division of Chile administered by a municipal council, headed by an alcalde who is directly elected every four years. The 2021-2024 mayor is Claudio Cumsille.