The Harney Basin is an endorheic basin in southeastern Oregon in the United States at the northwestern corner of the Great Basin. One of the least populated areas of the contiguous United States, it is located largely in northern Harney County, bounded on the north and east by the Columbia Plateau—within which it is contained, physiographically speaking—and on the south and west by a volcanic plain. The basin encompasses an area of 1,490 square miles (3,859 km2) in the watershed of Malheur Lake and Harney Lake. Malheur Lake is a freshwater lake, while Harney Lake is saline-alkaline.

Harney County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 7,495, making it the sixth-least populous county in Oregon. The county seat is Burns. Established in 1889, the county is named in honor of William S. Harney, a military officer of the period, who was involved in the Pig War and popular in the Pacific Northwest.