Lexington is a city in and the county seat of Holmes County, Mississippi, United States. The county was organized in 1833 and the city in 1836. The population was 1,731 at the 2010 census, down from 2,025 at the 2000 census. The estimated population in 2016 was 1,573. It has declined with the growth of industrial agriculture. Many people have left the rural county to seek work elsewhere.