Horn Lake is a city in DeSoto County, Mississippi, United States. It is located 1.2 mi (1.9 km) south of Memphis, Tennessee. The population was 26,736 at the 2020 census, making it the 13th most populous city in Mississippi.

DeSoto County is a county located on the northwestern border of the U.S. state of Mississippi. As of the 2020 census, the population was 185,314, making it the third-most populous county in Mississippi. Its county seat is Hernando.