Mosby Creek is a 21-mile (34 km) tributary of the Row River in Lane County, in the U.S. state of Oregon.

It begins at the confluence of the east and west forks of the creek near the Calapooia Divide and the border with Douglas County.

[7] Mosby Creek's east and west forks meet to form the main stem.

Named tributaries from source to mouth include Cove, Tom, Miles, Tones, Lilly, Brownie, and Shea creeks.

Below that are Simpson, Blue, Short, Fall, Kennedy, Smith, Perkins, Kizer, and Champion creeks.