Lewisburg is a city in and the county seat of Marshall County, Tennessee, United States. The population was 12,288 in 2020. Lewisburg is located in Middle Tennessee, fifty miles south of Nashville and fifty-two miles north of Huntsville, Alabama. Residents have access to the larger cities via nearby I-65 and U.S. 431, the latter of which connects Lewisburg to downtown Huntsville via Fayetteville.