Eldon is an unincorporated community and census-designated place (CDP) in Cherokee County, Oklahoma, United States. As of the 2020 census, Eldon had a population of 347. 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.