Tennessee Reef is a coral reef located within the Florida Keys National Marine Sanctuary. It lies to the southeast of Long Key. It consists of drowned (deep) spur-and-groove reef. Much of the reef is within a designated "Research Only" zone.

An unmanned reef light is located near the reef.

• Benthic Habitat Map

• NOAA National Marine Sanctuary Maps, Florida Keys East
• NOAA Website on Tennessee Reef
• NOAA Navigational Chart 11449