The People's Republic of Bulgaria (PRB; Bulgarian: Народна република България (НРБ) Narodna republika Bǎlgariya (NRB)) was the official name of the Bulgarian socialist republic. The Peoples Republic of Bulgaria existed from 1946 to 1990, when the Bulgarian Communist Party (BCP) ruled together with its coalition partner, the Bulgarian Agrarian National Union. Bulgaria was part of Comecon, a member of the Warsaw Pact and closely allied with the Soviet Union during the Cold War.

Bulgarian resistance movement during World War II deposed the Kingdom of Bulgaria administration in the Bulgarian coup d'état of 1944 which ended the country's alliance with the Axis powers and led to the People's Republic being established in 1946.

The BCP modelled its policies after those pioneered in the Soviet Union, transforming the country over the course of a decade from an agrarian peasant society into an industrialised socialist society. In the mid 1950s, after the death of Joseph Stalin, the conservative hardliners lost influence and a period of social liberalisation and stability under Todor Zhivkov followed with varying degrees of conservative or liberal influence over time thereafter. After a new energy and transportation infrastructure was constructed, by 1960 manufacturing became the dominant sector of the economy and Bulgaria became a major exporter of household goods and, later on, computer technologies, earning it the nickname of "Silicon Valley of the Eastern Bloc." The country's relatively high productivity levels and high scores on social development rankings made it a model for other socialist countries' administrative policies.

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