Usually abbreviated as KLIA, Kuala Lumpur International Airport is Malaysia's main international airport and is situated in Sepang, about 50 km outside the capital city, Kuala Lumpur. Its IATA airport code is KUL or KUL2. Built at a cost of some 3.5 billion dollars, KLIA was inaugurated in 1999, its slogan being Bringing the World to Malaysia and Malaysia to the World.

Connections to Kuala Lumpur are possible on the KLIA Express train (RM35 one way), via taxis (approximately RM60) or buses. Most tourists will opt for the train or a taxi.

The airport is the main hub to Malaysia Airlines, and half of the Kuala Lumpur-Singapore air connection operated by both Malaysia Airlines and Singapore Airlines.

In 2001 a Saudi Arabian Airlines Boeing 747 aircraft being taxied from the hangar to the gate before a flight back to Saudi Arabia suffered nose damage as it entered a monsoon drainage ditch. Fortunately, none of the six crew members on board at the time were injured. Other than that, the young airport has not seen any incidents.

Airlines serving this airport include:

The name Kuala Lumpur International Airport was previously used as an alternate name for the Sultan Abdul Aziz Shah Airport (SZB) in Subang.