Lexington is a city in Lafayette County, Missouri. The population was 4,726 at the 2010 census. It is the county seat of Lafayette County. Located in western Missouri, Lexington lies approximately 40 miles east of Kansas City and is part of the Greater Kansas City Metropolitan Area. It is the home of the Battle of Lexington State Historic Site, and of the former Wentworth Military Academy and College, which operated from 1880 to 2017.