Eldon is an unincorporated community in Cherokee County, Oklahoma, United States. The population was 368 at the 2010 census, a loss of 62.3 percent from 991 at the 2000 census, due largely to shrinkage of the CDP boundaries. It lies east of Tahlequah at the junction of U.S. Highway 62 and State Highway 51. The Eldon Post Office existed from March 20, 1911, until May 30, 1936. The community is said to have been named for Eldon, Illinois.