|False Washita River|
Map of the Washita River watershed
|Part of||Red River|
|Cities||Clinton, OK, Anadarko, OK, Chickasha, OK, Pauls Valley, OK, Wynnewood, OK, Davis, OK, Tishomingo, OK|
|- location||Roberts County, Texas|
The Washita River (Pawnee: Awaastatkiicuʾ ) is a river in Texas and Oklahoma, United States. The river is 295 miles (475 km) long and terminates into Lake Texoma in Johnston County (also Bryan County and Marshall County - ), Oklahoma and the Red River.
The Washita River crosses Hemphill County, Texas and enters Oklahoma in Roger Mills County. In Oklahoma it cuts through the Oklahoma Counties of: Roger Mills, Custer, Washita, Caddo, Grady, Garvin, Murray, Carter, and Johnston. Lake Texoma is the border between Bryan County and Marshall County.
When the river reaches the Arbuckle Mountains it drops 30 ft/mile as it cuts through Big Canyon, a limestone gorge 300 feet deep.
The Washita's river bed is made up of unstable mud and sand. The banks of the river and steeply incised and erosive, made up of red earth. This makes it one of the most silt-laden streams in North America. 
Along its path, the Foss Dam impounds the Washita River to create the huge Foss Reservoir. Several reservoirs along the Washita River valley hold the waters of small tributaries, including Fort Cobb Lake, Lake Chickasha, and Arbuckle Reservoir.
The Battle of Washita River (or Washita River Massacre) occurred on November 27, 1868 when Lt. Col. George Armstrong Custer’s 7th U.S. Cavalry attacked Black Kettle’s Cheyenne village on the Washita River (near present day Cheyenne, Oklahoma) at dawn.
General (later President) Zachary Taylor established Fort Washita near lower end of the river in 1842 to protect citizens of the Choctaw and Chickasaw Nations from the plains indians. The Fort was about 19 miles above where the Washita river runs into the Red River.
- "AISRI Dictionary Database Search--prototype version. "River", Southband Pawnee". American Indian Studies Research Institute. Retrieved 2012-05-26.
- Arthur C. Benke; Colbert E. Cushing (2005). Rivers of North America. Academic Press. p. 1144. ISBN 9780120882533.
- Johnston, Joseph; Randolph Marcy; William Whiting (1850). Reports of the Secretary of War: With Reconnaissances of Routes from San Antonio to El Paso. Union Office. p. 250.