In 1925 at the age of 18, he joined fellow students to stage a school sit-in to mourn the death of the famous patriotic scholar Phan Chu Trinh. About this time he developed interest in the Communist party and in the unification of Vietnam. In 1926, he traveled to Guangzhou in southern China to attend a training course run by Nguyễn Ái Quốc (later to be known as Hồ Chí Minh) before being admitted as a member of the Vietnam Revolutionary Youth Association, the predecessor of the Communist Party of Vietnam (CPV).
In 1929, he worked for the revolutionary association in Saigon. In the same year, he was arrested, tried by the French colonial authorities and sentenced to ten years in prison. He served the term in Poulo Condor Island Prison until 1936 when he was released under the general amnesty granted by the government of the Popular Front in France after its recent electoral successes.
He joined the Indochinese Communist Party in 1940 and then continued to take part in activities led by Hồ Chí Minh. After Hồ Chí Minh rose to power during the August Revolution in 1945, Phạm Văn Đồng was appointed minister of finance of the newly established government of the Democratic Republic of Vietnam (DRV), a position he occuped till 1954. Before he assumed the position of Minister of Finance, he was well known as head of the Vietnamese delegation to the Vietnam-France post-war negotiations at Fontainebleau (France) in May 1946.
Following the defeat of Japan, nationalist forces fought French colonial forces in the First Indochina War that lasted from 1945 to 1954. The French suffered a major defeat at the Battle of Dien Bien Phu in 1954 and peace was sought. In May 1954, he led the delegation of the Hồ Chí Minh government to the Geneva Conference. After intense negotiations a peace treaty was signed and the French forces withdrew from direct conflict with the newly-independent North Vietnam. He signed the peace accords with French Premier Pierre Mendès-France.
During 1954 he served as Vice-Premier and Minister of Foreign Affairs. At the 5th session of the DRV First National Congress (1955), Dong was appointed prime minister. He is well known for being one of the leaders of Vietnam during the war with the United States. He was known to have close links with the Chinese government, who helped fund the conflict with the United States. He was also one of the figures involved in peace talks to end the conflict under the administrations of Lyndon Baines Johnson and Richard Nixon.
In general, Phạm Văn Đồng was considered a staunch communist and a great nationalist leader; one of the most faithful disciples of Hồ Chí Minh and a major figure in Vietnam's fight for independence and unity. He was known as a politician who tried to maintain a neutral position in the various conflicts within the party, particularly after the unification of Vietnam in 1975. In a 1981 interview with Stanley Karnow, Phạm Văn Đồng remarked
"Yes, we defeated the United States. But now we are plagued by problems. We do not have enough to eat. We are a poor, underdeveloped nation. Vous savez, waging a war is simple, but running a country is very difficult.This pragmatism might explain how he stayed in the position of Prime Minister for 32 years until 1987, when his retirement was approved by the 6th National Party Congress.
Although retired from public office, he served as an adviser to the Party Central Committee from 1987 to 1997. He often urged the party to make greater efforts to stop corruption, which is still a widespread problem in Vietnam today. He gave advice on similar issues, even after his term as an advisor to the Central Committee had ended. During his last years he became extremely ill. He lost the ability to use his hands and had to have someone else write down his words on paper.
On May 2, 2000, the Vietnamese Communist Party and the Vietnamese government announced that Phạm Văn Đồng, former Politburo member, former prime minister, had died in Hanoi on April 29, 2000 after several months of serious illness at the age of 94. Commemoration and funeral service was held on May 6, 2000 in Hanoi.