The West Branch Piscataquis River is a 22 mi tributary of the Piscataquis River in Piscataquis County, Maine. Its source (45.3831°N, -69.7515°W) is in East Moxie, Somerset County (Maine Township 2, Range 4, BKP EKR). The river runs about 6 mi east, then 11 mi south, then 5 mi east to its confluence with the East Branch Piscataquis River in Blanchard to form the Piscataquis. The Appalachian Trail crosses the West Branch just below Bald Mountain Stream, and runs along the north bank of the river for about 4 mi in Blanchard, to the joining with the East Branch.