| Wajja River | |
| Map: | Abbay OSM.png |
| Mouth Coordinates: | 9.5106°N 36.6613°W |
| Name Other: | Waja |
| Country: | Ethiopia |
| Mouth: | Hanger River |
| Progression: | Hanger → Didessa → Blue Nile → Nile → Mediterranean Sea |
| River System: | Nile Basin |
The Wajja is a river of western Ethiopia. It is a tributary of the Hanger River, and part of the watershed of the Blue Nile.