Buin is a city and commune of Chile, in the Maipo Province, Metropolitan Region of Santiago, which forms part of Greater Santiago. It is a city composed of the towns of Maipo, Viluco, Linderos, Valdivia de Paine, Alto Jahuel, Los Guindos and El Recurso. Buin is located about 35 km (22 mi) south of Santiago in the Maipo Valley wine region.
Buin has a population of over 53,506 people. Buin also forms part of the wider Buin area which has a population of over 63,419 people.