| Brandenberger Ache | |
| Subdivision Type1: | Countries |
| Subdivision Name1: | Germany and Austria |
| Subdivision Type2: | States |
| Subdivision Name2: | Bavaria and Tyrol |
| Source1 Location: | Spitzingsee |
| Mouth Coordinates: | 47.4468°N 11.8977°W |
| Length: | 37.8km (23.5miles) |
| Basin Size: | 283km2 |
The Brandenberger Ache is a river of Bavaria, Germany, and of the Kufstein District, Tyrol, Austria.
It is a long left tributary of the Inn. It starts as the outflow of the Spitzingsee in southern Bavaria, and flows from north to south to the town of Rattenberg where it merges with the Inn.