The airline's development and expansion was seriously damaged by the Vietnam War (1954–1975). But it did manage to still operate a selected number of flights and incorporate some airframes to support diplomatic flights during the war. The Sud Aviation SE-210 Caravelle III, commonly referred to as the Caravelle, was officially introduced to the South Vietnamese flag carrier, Air Viet Nam, on August 31, 1964. This arrival marked a significant leap into the jet age for civil aviation in the region. Following the unification of Vietnam, the aircraft transitioned into the fleet of the newly formed Hang Khong Viet Nam (the precursor to the modern Vietnam Airlines) in 1976, though its service in the post-war era was short-lived due to a shift toward Soviet-manufactured equipment.

Other early aircraft operated by Air Viet Nam as it was known back then where the Douglas C-54D and the Yakovlev Yak-40. These tri-jets became the workhorses for domestic legs, such as flights between Qui Nhon and Ho Chi Minh City, throughout the 1980s and 1990s. (The type remained in service for over two decades until the final examples were retired and stored in 1999)

Following the war, its first international destination was Beijing, followed by Vientiane in 1976. During that year, the airline was known as General Department of Civil Aviation in Vietnam.

The Ilyushin Il-18, was a cornerstone of the early Vietnam Airlines fleet, it was officially introduced to service in 1970. The airline utilized the Il-18 to significantly expand its medium-haul capabilities. These Soviet-built turboprops remained the backbone of the carrier's international operations for over two decades, famously serving routes to destinations like Beijing and Vientiane.

Vietnam Airlines, also introduced the Boeing 707 as a foundational part of its international fleet during the late 1970s and 1980s. The aircraft remained a staple of Vietnam Airlines' long-haul operations throughout the 1980s. (By April 1995, official fleet records indicated that the airline still maintained two Boeing 707-300s in its inventory, before they were eventually phased out by newer widebodies like the Boeing 767).

In 1978, another important destination of Vietnam Airlines was added, with flights offered to Bangkok. The late 1980s and early 1990s saw the expansion of the network to Hong Kong, Kuala Lumpur, Manila and Singapore.

In 1990, the company initiated discussions regarding the incorporation of Western built aircraft into the fleet. Which was still banned, being one of the consequences after the war. However, the carrier had to cancel the acquisition of two Airbus A310s due to their use of US-manufactured engines. By July 1991, Vietnam Airlines organized a similar but more complicated deal with TEA Basle, who spent the rest of 1991 negotiating a deal with US authorities. Eventually, a solution stating that "[the Boeing 737] must be positioned outside Vietnam, with no logo or lettering of Vietnam Airlines. On these conditions, it could operate on behalf of Vietnam Airlines".

In December 1991, Cathay Pacific and Vietnam Airlines agreed on a 50–50 joint venture to operate between Hong Kong and Vietnam, as the airline's Tupolev Tu134 fleet did not meet Kai Tak Airport's noise restrictions.

Vietnam Airlines modernized its regional operations significantly during the early 1990s as it tried to transition from Soviet-era aircraft to Western-built turboprops. It was not able to buy Amercian planes yet, but European manufactures were able to trade with Vietnam. So did the airline purchased in mid-1992, the ATR 72 variant to serve domestic routes with lower passenger demand. The first ATR 72 was introduced to the fleet on May, 1992. (it went on to operate 26 units of the type between the smaller 42 and the 72 variants).

In October 1992, the Boeing 737 was supplemented with an Airbus A310. However, with repair issues after the aircraft sustained an engine failure it led Vietnam Airlines to switch from Airbus to Boeing. Hence, a Boeing 767-200ER, leased from Ansett Worldwide Aviation Services (AWAS), arrived in January 1993, and a Royal Brunei Airlines Boeing 767-300ER, arrived the following year.

In October 1993, the first Airbus A320-200 was incorporated over a two-year wet-lease contract with Air France. Vietnam Airlines by now had started discussions with Air France about a partnership, and the French carrier agreed to lease its Airbuses to Vietnam Airlines, and also to provide customer support and pilot/crew training. By that time the route network had further expanded internationally, seeing the incorporation of destinations such as Paris, Tokyo, Seoul, Taipei, Sydney, and Melbourne.

The airline became the flag carrier of Vietnam in 1993, after having completed a restructuring programme that was started four years earlier. In that year, the airline split from the Civil Aviation Administration of Vietnam (CAAV) and became a state enterprise. In February 1994, US President Bill Clinton lifted the trade embargo to allow Vietnam Airlines the ability to acquire Western-built aircraft. Consequently, Vietnam Airlines announced in April of the same year that it would be phasing out its inefficient Soviet planes. By April 1995, the fleet consisted of nine Airbus A320s (all of them leased from Air France), 11 Antonov An-24s, four ATR72s, two Boeing 707-300s, three Ilyushin Il-18s, nine Tupolev Tu-134s and three Yakovlev Yak-40s.

On 27 May 1995, the airline, along with a number of other aviation-related businesses, were incorporated to establish Vietnam Airlines Corporation. Two Fokker 70s were purchased in mid-1995, they were aimed at partly replacing the Tu134 fleet on domestic routes. In December 1995, discussions with GECAS for the lease of three additional, second hand Boeing 767-300ERs were under way; these ex-Continental Airlines aircraft would act as a replacement for the previous operated Boeing 767's.

In September 1996, Vietnam Airlines started offering business class services and in 1999, the airline launched its frequent-flyer program, Golden Lotus Plus. In February 1996, GECAS delivered the first of three Boeing 767-300ER to the carrier, on dry-lease for five years. In May 2001, the first Airbus A321 joined the airline, making for the replacement of older types and leased A320.

In December 2001, Vietnam Airlines signed a historic agreement with Boeing for the acquisition of its first ever US-built aircraft, four B777-200ER, signalling the start of trade under the Bilateral Trade Agreement between the two countries. During 2002, Vietnam Airlines considered a lease offer from Airbus for two Airbus A340-300s although it never materialised.

On October 20, 2002, Vietnam Airlines officially unveiled its "Golden Lotus" corporate identity, marking a sophisticated shift in its global branding that was fully implemented across the fleet on November 1, 2002. This transformation replaced the previous "stork and sun" emblem with a stylized golden lotus flower, a symbol of Vietnamese culture representing purity and resilience. The rebranding introduced a striking new livery characterized by a deep teal blue fuselage and a prominent gold lotus on the tail fin.

This overhaul was not merely aesthetic; it signalled the airline's modernization and its transition into a world-class carrier, coinciding with the arrival of its first Boeing 777-200ER aircraft on the 4th September 2003 and a commitment to elevated service standards.

In June 2005, Vietnam Airlines ordered four Boeing 787-8s. Twelve additional 787-8s were then ordered in late 2007, some of them to be directly acquired from the Boeing company. These new aircraft were to allow Vietnam Airlines to expand its network and replace some leased aircraft. In 2010 the airline switched its Boeing 787 order from the –8 to the –9 model.

On 20 June 2005, the airline launched direct services to Frankfurt after having discontinued services to Berlin. On 1 October 2007, the airline and VALC signed a memorandum of understanding for the purchase of ten Airbus A350 XWBs, and 20 additional Airbus A321s. It was also in 2007, that the airline received its first A330, until the newer equipment arrived. The Airbus A350s will supplement the Boeing 787s already ordered by the airline. The two companies also ordered five extra ATR 72-500s in December 2007. In August 2008, Vietnam Airlines added Nagoya, the airline's fourth point served in Japan besides Fukuoka, Osaka and Tokyo, to the route network.

In 2009, Vietnam Airlines and the Government of Cambodia established a joint venture, having 49% and 51% stockholding, respectively, with the goal of boosting tourism in Cambodia. The joint-venture was a new Cambodian national airline named Cambodia Angkor Air, which started flying in July the same year, using ATR-72 aircraft, and Airbus A321. Also in 2009, the carrier signed a deal for another 16 Airbus A321s plus two Airbus A350s, during the Paris Air Show. Vietnam Airlines joined SkyTeam on 10 June 2010. In February 2012, Vietnam Airlines boosted its stake in the low-cost carrier Jetstar Pacific Airlines to 70%, with Qantas holding the balance.

In late April 2012, the aircraft lessor ALC announced the placement of an order for eight Boeing 787-9s, which will be leased to Vietnam Airlines. In July 2014, a new route to Tokyo-Haneda from Hanoi was introduced. Vietnam Airlines received its first Airbus A350-900 in late June 2015, becoming the second operator of the type worldwide after Qatar Airways. In August 2015, the airline's first Boeing 787-9 entered the fleet. London operations were transferred from Gatwick to Heathrow in 2015, operating its new Boeing 787-9 aircraft.