The Pomme de Terre River is a tributary of the Minnesota River, 106 miles (170 km) long, in western Minnesota in the United States. Via the Minnesota River, it is part of the watershed of the Mississippi River, draining an area of 875 square miles (2,266 km²) in an agricultural region. The headwaters region of the Pomme de Terre River is the northernmost extremity of the Minnesota River's watershed.
In its upper course the river flows through a morainic region of numerous lakes, in a course characterized by meadows and wooded hills, as well as marshy stretches near areas where the river passes through lakes. The largest lakes on the river include Ten Mile Lake in Otter Tail County; Pomme de Terre and Barrett Lakes in Grant County; and Perkins Lake in Stevens County. The water levels of several lakes on the river's course are maintained by small dams. Downstream of Morris, the river flows on till plains between eroding banks and becomes increasingly turbid. According to the Minnesota Pollution Control Agency, approximately 81% of the land in the Pomme de Terre River's watershed is used for agriculture; of this area, half is used for the cultivation of corn and soybeans, and 43% for that of hay and small grains.