Adolfo Suárez Madrid–Barajas Airport (Spanish: Aeropuerto Adolfo Suárez Madrid-Barajas [aeɾoˈpweɾto aˈðolfo ˈswaɾeθ maˈðɾið βaˈɾaxas]) (IATA: MAD, ICAO: LEMD), commonly known as Madrid–Barajas Airport, is the main international airport serving Madrid in Spain. At 3,050 ha (7,500 acres) in area, it is the second-largest airport in Europe by physical size behind Paris–Charles de Gaulle Airport. In 2019, 61.8 million passengers travelled through Madrid–Barajas, making it the country's busiest airport as well as Europe's sixth-busiest.

The airport opened in 1931 and has grown to be one of Europe's most important aviation centres. Within the city limits of Madrid, it is 9 km (6 mi) from the city's financial district and 13 km (8 mi) northeast of the Puerta del Sol or Plaza Mayor de Madrid, Madrid's historic centre. The airport name derives from the adjacent district of Barajas, which has its own metro station on the same rail line serving the airport. Barajas serves as the gateway to the Iberian peninsula from the rest of Europe and the world and is a key link between Europe and Latin America. Following the death of former Spanish Prime Minister, Adolfo Suárez, in 2014, the Spanish Ministry of Public Works and Transport announced that the airport was to be renamed Aeropuerto Adolfo Suárez, Madrid–Barajas. The airport is the primary hub and maintenance base for Iberia and Air Europa. Consequently, Iberia is responsible for more than 40% of Barajas' traffic. The airport has five passenger terminals: T1, T2, T3, T4 and T4S.