| Thon | |
| Map: | Ton (rivière).png |
| Mouth Coordinates: | 49.9055°N 3.9084°W |
| Subdivision Type1: | Country |
| Length: | 56.3km (35miles) |
| Source1 Elevation: | 273m (896feet) |
The Thon or Ton is a small river in northern France. It is a tributary of the river Oise, which flows into the Seine. It crosses the Ardennes and Aisne departments and is the central river of the Thiérache.