Fernandina Beach Municipal Airport (ICAO: KFHB, FAA LID: FHB, formerly 55J) is a city-owned public-use airport located on Amelia Island three nautical miles (6 km) south of the central business district of Fernandina Beach, a city in Nassau County, Florida, United States. It is designated as a reliever airport for Jacksonville International Airport.

Fernandina Beach Municipal Airport was developed as a training facility by the United States Navy during World War II, serving as Outlying Field Fernadina Beach (OLF Fernadina Beach) to the Naval Air Station Jacksonville complex. The airport was transferred to the City of Fernandina Beach in 1946 and is designated as a general aviation reliever airport for Jacksonville International Airport. It is occasionally used as a practice airfield by U.S. Navy helicopters from NAS Jacksonville and Naval Station Mayport and by U.S. Coast Guard and Florida Army National Guard helicopters from Cecil Field.