Pakistan International Airlines (Urdu: پاکستان انٹرنیشنل ایئر لائنز; abbreviated PIA, Urdu: پی‌آئی‌اے) is an international airline that serves as the national flag carrier of Pakistan under the administrative control of the Secretary to the Government of Pakistan for Aviation. Its central hub is Karachi's Jinnah International Airport, while Allama Iqbal International Airport in Lahore and Islamabad International Airport serve as secondary hubs.

PIA was founded on 29 October 1946 as Orient Airways, and was initially based in Calcutta, British India, before shifting operations to the newly independent state of Pakistan in 1947. Orient Airways was nationalised to form the Pakistan International Airlines Corporation (PIAC). The new airline commenced international services in 1955 to London, via Cairo and Rome. PIA, in 1964 became the first non-Communist airline to fly to China. The airline played a vital role in the establishment of Emirates Airline in 1985. In 2004, PIA became the launch customer of the Boeing 777-200LR. On 10 November 2005, PIA used the Boeing 777-200LR to complete the world's longest nonstop flight by a commercial airliner. This flight lasted 22 hours and 22 minutes on the eastbound route between Hong Kong and London.

PIA is Pakistan's largest airline and operates a fleet of 30+ aircraft. The airline operates nearly 50 flights daily, servicing 20 domestic destinations and 27 international destinations across Asia, Europe, the Middle East and North America. In addition to commercial flight operations, PIA also owns the Sofitel Paris Scribe Hotel in Paris, and The Roosevelt Hotel in New York City. The airline operates a frequent flier programme, PIA Awards +, and has several codeshare and interline agreements. However, it is not part of any airline alliance.

On 30 June 2020, PIA was banned from flying in European airspace initially for six months, starting on 1 July 2020, and then indefinitely after EASA determined that the airline was not capable of certifying and overseeing its operators and aircraft in accordance with applicable international standards. This decision was made soon after it was revealed that at least a third of all pilot's licenses issued in Pakistan were not genuine. By 9 July 2020, the airline was also banned by the United Kingdom and the United States.