| Marten River | |
| River | |
| Country | Canada |
|---|---|
| Province | Ontario |
| Region | Northeastern Ontario |
| District | Nipissing |
| Municipality | Temagami |
| Source | Lower Redwater Lake |
| - elevation | 300 m (984 ft) |
| - coordinates | 46°53′3″N 79°38′2″W / 46.88417°N 79.63389°W |
| Mouth | Red Cedar Lake |
| - elevation | 280 m (919 ft) |
| - coordinates | 46°43′49″N 79°53′28″W / 46.73028°N 79.89111°WCoordinates: 46°43′49″N 79°53′28″W / 46.73028°N 79.89111°W |
| Length | 46 km (29 mi) |
The Marten River is a river in Nipissing District, Ontario, Canada. Situated in the Municipality of Temagami, it begins at the southern end of Lower Redwater Lake at an elevation of 300 m (980 ft). It flows westwards to the hamlet of Marten River then to Red Cedar Lake where it is 280 m (920 ft) in elevation. The Marten River has a total length of 46 km (29 mi).