| Guapi Island | |
| Location: | Ranco Lake |
| Coordinates: | -40.2222°N -72.3783°W |
| Highest Mount: | Cerro Puirre (152m (499feet) above Ranco Lake) |
| Elevation M: | 217 |
| Country: | Chile |
| Country Admin Divisions Title: | Region |
| Country Admin Divisions: | Los Ríos |
| Country Admin Divisions Title 1: | Province |
| Country Admin Divisions 1: | Ranco |
| Country Admin Divisions Title 2: | Commune |
| Country Admin Divisions 2: | Futrono |
| Population: | ~900 |
| Ethnic Groups: | Huilliche |
Guapi or Huapi (Mapudungun for island) is an island in Ranco Lake, southern Chile. Administratively it belongs to the commune of Futrono in Los Ríos Region.