Quang, who was first elected president in early April by the outgoing assembly, won 485 votes from the 494 deputies of the Communist Party-dominated assembly, the government said on its website.
Vietnam's top leaders include the Communist Party chief, the president and the prime minister, though the position of president is more ceremonial than the other two.
In his acceptance speech today, which was broadcast live on state television, Quang pledged to "speed up the reform process in a comprehensive and synchronised manner, engage in proactive integration, build a growing strong and prosperous nation and heighten Vietnam's position in the international arena."
Quang, who was the minister of public security before becoming president, also vowed to "firmly defend the sacred national independence, sovereignty and territorial integrity" and to "maintain political and social stability and create a peaceful environment for national construction."
The National Assembly deputies, who were elected in general elections in May, are scheduled to reappoint Prime Minister Nguyen Xuan Phuc tomorrow.
