Huilo-Huilo Biological Reserve (Spanish pronunciation: [ˈwilo ˈwilo] audio , Pronounced: /ˈwiːloʊ ˈwiːloʊ/ WEEL-oh-WEEL-oh) is a private for profit natural reserve and ecotourism project in southern Chile. The reserve was created in 1999 and includes 600 km2 (232 sq mi) of native forest in Chile dedicated to wildlife conservation and tourism. The reserve is owned by the businessman Víctor Petermann who bought it in the 1990s, and was prior to the land sellings of the late Pinochet Regime part of Complejo Forestal y Maderero Panguipulli.
The reserve is located north east of the Mocho-Choshuenco volcano in Los Ríos Region. The main entrance is on the international gravel road that connects Panguipulli, with San Martín de los Andes, Argentina.