Watonga Lake is a reservoir in Blaine County, Oklahoma. It is north of Watonga, Oklahoma. Constructed by the Oklahoma Department of Wildlife Conservation (ODWC) in 1955, is adjacent to Roman Nose State Park, with which it shares many recreational facilities.
The name Watonga was that of an Arapaho tribe leader (also given as woteen-kotuh'oo) meaning "black coyote."
The lake is small, compared to many of the other lakes and reservoirs in the state. The surface area is , the rated capacity is , the shore line is , average depth is and the maximum depth is The elevation is .