| Seiche | |
| Pushpin Map: | France Bretagne#France |
| Mouth Coordinates: | 47.9972°N -1.7554°W |
| Subdivision Type1: | Country |
| Length: | 97.3km (60.5miles) |
The Seiche is a 97.3km (60.5miles) long river in western France located in the departments of Mayenne (Pays de la Loire) and Ille-et-Vilaine (Brittany). It is a left tributary of the river Vilaine. It flows into the Vilaine near Bruz, south of Rennes.