| Afon Fathew | |
|---|---|
 View of the Afon Fathew valley | |
 | |
| Location | |
| Country | Wales |
| Region | Gwynedd |
| Physical characteristics | |
| Source | |
| • location | Gwynedd |
| Mouth | |
• location | River Dysynni |
| Discharge | |
| • location | Dysynni |
The Afon Fathew (English: River Mathew/Fathew) is a river in Gwynedd, north-west Wales. The river is downstream from the Dolgoch Falls which is a popular nature site, and is followed for much of its course by the Talyllyn Railway.