Giap died at a military hospital in Hanoi, where he had been living since 2009, Tuoitrenews reported.
The general joined Ho Chi Minh's nationalist Viet Minh forces while he was living in exile in China in the 1940s, The Wall Street Journal reported.
Although Giap had no military training, he became a top military commander and returned to his home country in 1944 to force the French out of Vietnam during the First Indochina War.
Giap went on to lead the 57-day battle of Dien Bien Phu in 1954, which ended with France surrendering.
In a 1999 interview with the U.S. Public Broadcasting System, Giap said the victory was "the first great victory for a weak, colonized people struggling against the full strength of modern Western forces. This is why it was the first great defeat for the West. It shook the foundations of colonialism and called on people to fight for their freedom."
Giap stayed at his post for the Vietnam War, which resulted in a stalemate with the United States, forcing American troops out of the conflict, and ultimately uniting North and South Vietnam, The New York Times reported.
Following the wars, Giap campaigned for an economic overhaul and closer relations with the United States. Most recently he was fighting to protect Vietnam's fragile ecology that has been damaged by strip mining.