Attala County is a county located in the U.S. state of Mississippi. As of the 2020 census, the population was 17,889. Its county seat is Kosciusko. Attala County is named for Atala, a fictional Native American heroine from an early-19th-century novel of the same name by François-René de Chateaubriand.

Kosciusko is a city in Attala County, Mississippi, United States. The population was 7,402 at the 2010 census. It is the county seat of Attala County.