| Oelse | |
| Source1 Location: | Möschensee |
| Mouth Location: | Spree near Beeskow |
| Subdivision Type1: | Country |
| Subdivision Name1: | Germany |
| Subdivision Type2: | State |
| Subdivision Name2: | Brandenburg |
| Subdivision Type3: | District |
| Subdivision Name3: | Oder-Spree |
| Source1 Elevation: | 68.3m (224.1feet) |
| Mouth Elevation: | 40.4m (132.5feet) |
The Oelse is a river in the district Oder-Spree, Brandenburg, Germany. It is situated in the Schlaube Valley Nature Park and runs from the Möschensee (lake) in the east from Groß Muckrow (part of Friedland) to the river Spree near Beeskow. Its name derives from the sorbian ol'ša (English: alder tree).