Sylvania is a town in DeKalb County, Alabama, United States. It incorporated in October 1967. At the 2010 census the population was 1,837, up from 1,186 in 2000. Sylvania is located atop Sand Mountain. Sylvania was incorporated in 1967. The post office /town hall was built in 1977.

DeKalb County is a county located in the northeastern part of the U.S. state of Alabama. As of the 2020 census, the population was 71,608. Its county seat is Fort Payne, and it is named after Major General Baron Johan DeKalb. DeKalb County is part of the Huntsville-Decatur-Albertville, AL Combined Statistical Area.