The Cowanesque River is a 41.4-mile-long (66.6 km)[2] tributary of the Tioga River in Potter and Tioga counties, Pennsylvania, and Steuben County, New York, in the United States.

[3] The name of the Cowanesque River is of Native American origin, derived either from Go-wan-is-que ("briary or thorn bushy"), or from Ka-hwe-nes-ka ("on the long island").

[4] In Tioga County, the Cowanesque Dam was constructed by the US Army Corps of Engineers in 1980.

The dam created Cowanesque Lake, which helps prevent flooding within the valley.

The 1,085-acre (4.39 km2) lake also facilitates various forms of recreation; the Tompkins Recreation Area and Campground is located along the lake's north shore, and the south shore hosts two day-use areas.