The People's Republic of Kampuchea (PRK; Khmer: សាធារណរដ្ឋប្រជាមានិតកម្ពុជា Sathéaranakrâth Pracheameanit Kâmpŭchéa) was founded in Cambodia by the Salvation Front, a group of Cambodian communists dissatisfied with the Khmer Rouge, after the overthrow of Democratic Kampuchea, Pol Pot's government. Brought about by an invasion from the Socialist Republic of Vietnam, which routed the Khmer Rouge armies, it had Vietnam and the Soviet Union as its main allies.

The PRK failed to secure United Nations endorsement due to the diplomatic intervention of the People's Republic of China, the United Kingdom, the United States, and the ASEAN countries. The Cambodian seat at the United Nations was held by the Coalition Government of Democratic Kampuchea, which was the Khmer Rouge in coalition with two non-communist guerrilla factions. However, the PRK was considered the de facto government of Cambodia between 1979 and 1993, albeit with limited international recognition.

Beginning May 1989, the PRK restored the name "Cambodia" by renaming the country, State of Cambodia (SOC) (Khmer: រដ្ឋកម្ពុជា, Rath Kâmpŭchéa) during the last four years of its existence in an attempt to attract international sympathy. It retained, however, most of its leadership and one-party structure, while undergoing a transition and eventually giving way to the restoration of the Kingdom of Cambodia. The PRK/SOC existed as a socialist state from 1979 until 1991, the year in which the ruling single party abandoned its Marxist-Leninist ideology.

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