Wittman Regional Airport (IATA: OSH, ICAO: KOSH, FAA LID: OSH) is a county-owned public-use airport located two nautical miles (4 km) south of the central business district of Oshkosh, a city in Winnebago County, Wisconsin, United States.

Until 1980, Wittman boarded more passengers than nearby Appleton International Airport, and was the commercial air hub of the Fox Cities.

Service was subsidized by the Essential Air Service program until March 2003,[11][12] when it was terminated due to federal law not allowing a subsidy over $200 per passenger for communities located within 210 miles of the nearest large or medium hub airport (Milwaukee Mitchell International Airport, a medium hub serving Milwaukee).

[13] Wittman Regional Airport covers an area of 1,392 acres (563 ha) at an elevation of 809 feet (247 m) above mean sea level.

In particular, Knapp Street (running parallel to the runways) has been permanently closed near the airport to facilitate the expansion of the grounds in that area (for the annual EAA AirVenture.)

The EAA has a hangar on the northwestern side of the field which does most of the maintenance, overhaul, and restoration to their many aircraft including: Bell 47, Ford Trimotor, B-25, Cessna 162s, RV-12s, and its B-17 (Aluminum Overcast).

For the week of AirVenture Oshkosh (known locally as "The Airshow" or "The Fly-in"), Wittman Regional is the world's busiest airport by traffic movements.