El Dorado is a city situated along the Walnut River in the central part of Butler County, located in south-central Kansas, in the central United States. The population was estimated to be 12,659 in the year 2005. It is the county seat and most populous city of Butler County. El Dorado is included in the Wichita Metropolitan Statistical Area. El Dorado apartments for rent comparison page shows most up to date rent information on El Dorado apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.