Boulder Junction Airport (ICAO: KBDJ, FAA LID: BDJ) is a public use airport located two nautical miles (4 km) north of the central business district of Boulder Junction, a town in Vilas County, Wisconsin, United States. It is owned by the Town of Boulder Junction.

Although many U.S. airports use the same three-letter location identifier for the FAA and IATA, this facility is assigned BDJ by the FAA but has no designation from the IATA (which assigned BDJ to Syamsudin Noor Airport in Banjarmasin, South Kalimantan, Indonesia).