The Swanson River is a river in Sudbury District in northeastern Ontario, Canada.

[1] It is in the James Bay drainage basin, begins south of Mageau Lake and is a left tributary of the Chapleau River.

The river begins in geographic Marshall Township,[2] and flows north to Mageau Lake, where it enters geographic Mageau Township.

[3] It heads northeast into geographic Manning Township,[4] continues northeast into geographic Floranna Township[5] followed by geographic Sadler Township.

It enters geographic Lipsett Township,[6] takes in the right tributary Little Swanson River, heads east into geographic Copperfield Township,[7] and reaches its mouth at Schewabik Lake on the Chapleau River.