The People's Movement for the Liberation of Angola (Portuguese: Movimento Popular de Libertação de Angola, abbr. MPLA), from 1977 to 1990 called the People's Movement for the Liberation of Angola – Labour Party (Portuguese: Movimento Popular de Libertação de Angola – Partido do Trabalho), is an Angolan social democratic political party. The MPLA fought against the Portuguese Army in the Angolan War of Independence from 1961 to 1974, and defeated the National Union for the Total Independence of Angola (UNITA) and the National Liberation Front of Angola (FNLA) in the Angolan Civil War. The party has ruled Angola since the country's independence from Portugal in 1975, being the de facto government throughout the civil war and continuing to rule afterwards.

The articulation for the founding of the MPLA took place, mainly, within two political organizations: the Party of the United Struggle for Africans in Angola (PLUAA), founded in 1953 by Viriato da Cruz and Matias Miguéis, which operated incipiently until 1954 due to a lack of mass mobilization, being overshadowed by other anti-colonial political and cultural nationalist groups that already operated in Angola and Portugal, and; the Angolan Communist Party (PCA), founded in December 1955 as a Luanda-based cell of the Portuguese Communist Party (PCP), initially grouping together prominent leaders of Angolan nationalism, such as Viriato da Cruz, Ilídio Machado, Mário António and António Jacinto, and, soon after, Lúcio Lara, Mário Pinto de Andrade and Joaquim Pinto de Andrade.

The PCA leadership realized that the growth of the nationalist struggle was hindered by the reluctance to accept the Marxist-Leninist class struggle that the party proposed, as well as by the persecution imposed by the Estado Novo regime on any organization of a communist or socialist nature. Viriato da Cruz, a member of both organizations, arranged for the merger and organization of the PCA with the PLUAA — the latter a non-communist party and, from mid-1955 onwards, already with a mass popular organization. Discussions advanced towards the formation of a broad-front nationalist movement that would encompass diluted organizations within it, without using symbols or explicitly disseminating Marxist-Leninist theories. Thus, on December 10, 1956, in a meeting at Ilídio Machado's house in Luanda, he, Viriato da Cruz and Mário Pinto de Andrade wrote the "Manifesto of 1956" for a "broad Popular Movement for the Liberation of Angola", as a program for regrouping nationalist struggles. In addition to the aforementioned names who led the PLUAA and the PCA, the following joined the manifesto creating the MPLA: Liceu Vieira Dias, Chico Machado, Germano Joy Gomes, Manuel dos Santos Capicua, Noé Saúde, Deolinda Rodrigues, Manuel Bento Ribeiro, Paulo Teixeira Jorge, Adriano Sebastião Kiwima and Amílcar Cabral. Ilídio Machado, a key member of the PCA and the African National League, was elected the first president of the MPLA, remaining in office until his arrest in 1959. Anticipating the siege by the Portuguese political police, Ilídio Machado ordered the withdrawal of part of the MPLA leadership from Luanda by September 1957, entrusting Mário de Andrade and Viriato da Cruz with the formation of a foreign relations nucleus and headquarters in exile in Paris and Frankfurt am Main. Ilídio Machado, Joaquim de Andrade, Sebastião Kiwima and Manuel Pedro Pacavira remained in Luanda leading the actions of the MPLA. When arrested, Ilídio Machado was replaced by the secretary-general Mário de Andrade, who held the position in exile between 1959 and 1960; of leadership, only António Jacinto, Pacavira and Joaquim de Andrade remained in Angola coordinating the activities of the movement that still had few militants. Other groups later merged into MPLA, such as the Movement for the National Independence of Angola (MINA) and the Democratic Front for the Liberation of Angola (FDLA).

The MPLA's core base includes the Ambundu ethnic group and the educated intelligentsia of the capital city, Luanda. The party formerly had links to European and Soviet communist parties, but today is a full-member of the Socialist International grouping of social democratic parties. The armed wing of MPLA was the People's Armed Forces for the Liberation of Angola (FAPLA). The FAPLA later (1975–1991) became the national armed forces of the country when the MPLA took control of the government.

In 1961, the MPLA joined the African Party for the Independence of Guinea and Cape Verde (PAIGC), its fraternal party in Guinea-Bissau and Cabo Verde, in direct combat against the Portuguese empire in Africa. The following year, the expanded umbrella group Conference of Nationalist Organizations of the Portuguese Colonies (CONCP) replaced FRAIN, adding FRELIMO of Mozambique and the CLSTP, forerunner of the Movement for the Liberation of São Tomé and Príncipe (MLSTP).

In the early 1970s, the MPLA's guerrilla activities were reduced, due to the fierce counter-insurgency campaigns of the Portuguese military. At the same time, internal conflicts caused the movement to temporarily split into three factions (Ala Presidencialista or Presidentialist Wing, Revolta Activa or Active Revolt, and Revolta do Leste or Eastern Revolt). By 1974/75, this situation had been overcome with renewed cooperation, but it scarred the party.

The Carnation Revolution in Lisbon, Portugal in 1974 established a military government. It promptly ceased anti-independence fighting in Angola and agreed to transfer power to a coalition of three pro-independence Angolan movements.

The coalition quickly broke down and the newly independent Angola broke into a state of civil war. Maintaining control over Luanda and the lucrative oil fields of the Atlantic coastline, Agostinho Neto, the leader of the MPLA, declared the independence of the Portuguese Overseas Province of Angola as the People's Republic of Angola on 11 November 1975, in accordance with the Alvor Accords.