The Việt Nam Quốc Dân Đảng (Vietnamese: [vìət naːm kwə́wk zən ɗa᷉ːŋ]; chữ Hán: 越南國民黨; Vietnamese Nationalist Party) or the Nationalist Party of Vietnam, abbreviated VNQDĐ or Việt Quốc, was a nationalist and moderate socialist political party that sought independence from French colonial rule in Vietnam during the early 20th century. Its origins lie in the mid-1920s, when a group of young Hanoi-based intellectuals began publishing revolutionary material. In 1927, after the publishing house failed because of French harassment and censorship, the VNQDD was formed under the leadership of Nguyễn Thái Học. Modelling itself on the Kuomintang of Nationalist China (the same three characters in chữ Hán: 國民黨) the VNQDD gained a following among northerners, particularly teachers and intellectuals. The party, which was less successful among peasants and industrial workers, was organised in small clandestine cells.
From 1928, the VNQDD attracted attention through its assassinations of French officials and Vietnamese collaborators. A turning point came in February 1929 with the Bazin assassination, the killing of a French labour recruiter widely despised by local Vietnamese people. Although the perpetrators' precise affiliation was unclear, the French colonial authorities held the VNQDD responsible. Between 300 and 400 of the party's approximately 1,500 members were detained in the resulting crackdown. Many of the leaders were arrested, but Học managed to escape.
In late 1929, the party was weakened by an internal split. Under increasing French pressure, the VNQDD leadership switched tack, replacing a strategy of isolated clandestine attacks against individuals with a plan to expel the French in a single blow with a large-scale popular uprising. After stockpiling home-made weapons, the VNQDD launched the Yên Bái mutiny on February 10, 1930 with the aim of sparking a widespread revolt. VNQDD forces combined with disaffected Vietnamese troops, who mutinied against the French colonial army. The mutiny was quickly put down, with heavy French retribution. Học and other leading figures were captured and executed and the VNQDD never regained its political strength in the country.
Some remaining factions sought peaceful means of struggle, while other groups fled across the border to Kuomintang bases in the Yunnan province of China, where they received arms and training. During the 1930s, the party was eclipsed by Ho Chi Minh's Indochinese Communist Party (ICP). Vietnam was occupied by Japan during World War II and, in the chaos that followed the Japanese surrender in 1945, the VNQDD and the ICP briefly joined forces in the fight for Vietnamese independence. However, after a falling out, Ho purged the VNQDD, leaving his communist-dominated Viet Minh unchallenged as the foremost anti-colonial militant organisation. As a part of the post-war settlement that ended the First Indochina War, Vietnam was partitioned into two zones. The remnants of the VNQDD fled to the capitalist south, where they remained until the Fall of Saigon in 1975 and the reunification of Vietnam under communist rule. Today, the party survives only among overseas Vietnamese.