Buyant-Ukhaa International Airport (Mongolian: Буянт-Ухаа олон улсын нисэх буудал), formerly called Chinggis Khaan International Airport from 2005 to 2020 (IATA: ULN, ICAO: ZMUB), is a semi-operational international airport serving Ulaanbaatar, Mongolia, situated 18 km (11 mi) southwest of the capital. Largely replaced by a new airport, it currently functions as a backup airport for the former, with a view to being used for flight training as well as for special, charter, and government flights.

The airport was first established as Buyant-Ukhaa Central Airport on 19 February 1957. In 1958, international flights began with flights to Irkutsk and Beijing using Ilyushin Il-14 aircraft. Regular flights from the airport started in 1961.

The terminal was upgraded to make it suitable for international traffic in 1986.

Following the Mongolian Revolution of 1990 and between 1994 and 1997 a further major upgrade of construction and air navigation was achieved with the assistance of the Asian Development Bank, making the airport compliant with ICAO standards. The US$50 million construction project was carried out by the successful bidder: a German / English joint venture of Philipp Holzmann and Wimpey Asphalt.

The airport was renamed after Chinggis Khaan (Genghis Khan) to Chinggis Khaan International Airport to celebrate the 800th anniversary of the establishment of a Mongolian State on 21 December 2005. The airport achieved steady growth during the 2000s, with passenger numbers first reaching 1 million in 2012, and reaching a peak of 1.6 million in 2019, before collapsing due to the COVID-19 pandemic.

The airport was replaced by the opening of the new Ulaanbaatar International Airport in 2021. Buyant-Ukhaa is somewhat restricted, the single runway is used in one direction for arriving aircraft and in the opposite direction for departures. The new airport significantly expands capacity, and is located at the Khoshigt Valley, 52 kilometres (32 mi) south of Ulaanbaatar city center. With the new airport named Chinggis Khaan International Airport, Buyant-Ukhaa reverted to its former name on July 1, 2020.

In May 2023, it hosted the Buyant-Ukhaa Airshow, the first airshow exhibited in the country.

Airlines	Destinations
Aero Mongolia	Altai, Dalanzadgad, Irkutsk, Khovd, Mörön, Ölgii, Ovoot, Oyu Tolgoi, Tavan Tolgoi, Tianjin, Ulaangom
Aeroflot	Moscow–Sheremetyevo
Air Busan	Busan
Air China	Beijing–Capital, Hohhot
Asiana Airlines	Seoul–Incheon
Eznis Airways	Hong Kong
Hunnu Air	Bayankhongor, Choibalsan, Dalanzadgad, Khovd, Mörön, Ölgii, Ulaangom, Ulan-Ude
IrAero	Seasonal: Ulan-Ude
Korean Air	Seoul–Incheon
MIAT Mongolian Airlines	Beijing–Capital, Berlin, Hong Kong, Seoul–Incheon, Tokyo–Narita Seasonal: Bangkok–Suvarnabhumi
SCAT Airlines	Nur-Sultan
Tianjin Airlines	Tianjin
Turkish Airlines	Istanbul

Annual traffic

	Passengers	Change	Movements	Cargo (tons)	Change
2007	599,555	0+9.6%	9,297	3,299	0+11.2%
2008	596,765	0-0.5%	9,552	3,500	0+2.7%
2009	532,861	0-10.7%	8,330	2,970	0-12.8%
2010	665,055	0+24.8%	11,678	3,922	0+40.2%
2011	885,885	0+33.2%	14,940	5,452	0+27.9%
2012	1,098,865	0+24.0%	17,465	5,709	0+16.9%
2013	1,106,704	0+0.7%	16,468	5,825	0-5.7%
2014	1,019,102	0-7.9%	13,178	4,955	0-20.0%
2015	955,867	0-6.2%	10,985	4,710	0-4.9%
2016	1,023,045	0+7.0%	11,682	4,852	0+3.0%
2017	1,251,775	0+22.3%	13,594	5,022	0+15.0%
2018	1,422,498	0+13.6%	14,899	5,339	0+6.3%
2019	1,621,571	0+14.0%	18,109	5,406	0+1.3%
2020	447,478	0-72.4%	7,284	2,501	0-53.7%
Sources: Civil Aviation Administration of Mongolia

Busiest domestic routes from Ulaanbaatar (2019)

Rank	Airport	Passengers	Airlines
1	Oyu Tolgoi, Ömnögovi	275,466	Aeromongolia, Hunnu Air, MIAT
2	Ölgii, Bayan-Ölgii	23,960	Aeromongolia, Hunnu Air
3	Khovd, Khovd	23,650	Aeromongolia, Hunnu Air
4	Mörön, Khövsgöl	16,863	Aeromongolia, Hunnu Air
5	Ulaangom, Uvs	15,177	Aeromongolia, Hunnu Air
6	Ovoot, Ömnögovi	14,873	Aeromongolia, Hunnu Air
7	Dalanzadgad, Ömnögovi	13,324	Aeromongolia, Hunnu Air
8	Altai, Govi-Altai	11,055	Aeromongolia, Hunnu Air
9	Choibalsan, Dornod	6,121	Aeromongolia, Hunnu Air
10	Uliastai, Zavkhan	3,409	Aeromongolia
Sources: Civil Aviation Administration of Mongolia

Busiest international routes from Ulaanbaatar (2019)

Rank	Airport	Scheduled passengers	Carriers
1	Seoul–Incheon, Korea	387,740	MIAT, Asiana, Korean Air
2	Beijing, China	214,567	MIAT, Air China
3	Moscow, Russia	94,890	MIAT, Aeroflot
4	Hong Kong	88,846	Eznis, MIAT
5	Tokyo, Japan	79,118	MIAT
6	Busan, South Korea	64,498	MIAT, Air Busan
7	Erenhot, China	50,608	Hunnu Air
8	Istanbul, Turkey	36,881	Turkish Airlines
9	Berlin, Germany	17,072	MIAT
10	Hohhot, China	15,913	Aeromongolia
Sources: Civil Aviation Administration of Mongolia

The airline Aero Mongolia has its head office on the third floor of the main airport building. The Air Accident Investigation Bureau Mongolia has its head office on the airport property. There is also one cargo hangar.

• List of airports in Mongolia
• List of airlines of Mongolia

• Official website
• Civil Aviation Authority of Mongolia
• Aeronautical Information Publication
• Current weather for ZMUB at NOAA/NWS
• Accident history for ULN at Aviation Safety Network