Boulder Municipal Airport (IATA: WBU, ICAO: KBDU, FAA LID: BDU) is a public airport located 3 miles (4.8 km) northeast of the central business district of Boulder, a city in Boulder County, Colorado, United States. It is owned by the City of Boulder and used almost exclusively for general aviation. Its location in the foothills of the Rockies east of the continental divide gives excellent conditions for soaring, and there is extensive gliding activity. It is the base of the Soaring Society of Boulder.

Founded in 1928, Boulder Municipal Airport is Colorado's oldest operating public airport.

Some college basketball teams fly into Boulder, rather than Denver International Airport, for games vs. the University of Colorado. College football teams playing at Boulder must fly into DIA, approximately 40 miles east, since Boulder is not equipped to handle the large jets chartered by those squads.

Most U.S. airports use the same three-letter location identifier for the FAA and IATA, but Boulder Municipal is BDU (formerly 1V5) to the FAA and WBU to the IATA (which assigned BDU to Bardufoss Airport in Bardufoss, Norway).