Nanafalia is an unincorporated community and census-designated place in Marengo County, Alabama, United States. As of the 2020 census, its population was 75, down from 94 at the 2010 census. The community is located on a ridge above the Tombigbee River, and the name is derived from the Choctaw words for long hill. Nanafalia has a post office with a zip code of 36764.