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).

This article related to a river in Northern Ontario, Canada is a stub.