| Köthener See | |
| Location: | Landkreis Dahme-Spreewald, Brandenburg |
| Pushpin Map: | Brandenburg |
| Coords: | 52.0804°N 13.8119°W |
| Inflow: | Randkanal (Wasserburger Spree), Dahme-Umflutkanal |
| Outflow: | Dahme-Umflutkanal |
| Basin Countries: | Germany |
| Length: | 2250m (7,380feet) |
| Width: | 1km (01miles) |
| Area: | 1.48km2 |
| Max-Depth: | 2m (07feet) |
| Elevation: | 43m (141feet) |
Köthener See is a lake in Landkreis Dahme-Spreewald, Brandenburg, Germany. It lies at an elevation of 43 m, and has a surface area of 1.48 km². It is located in the municipality of Märkisch Buchholz, Dahme-Spreewald district.