The Bulgarian Communist Party was the ruling party of the People's Republic of Bulgaria from 1946 until 1990 when it ceased to be a Communist state. The Bulgarian Communist Party had dominated the Fatherland Front coalition that took power in 1944, late in World War II, after it led a coup against Bulgaria's fascist government in conjunction with the Red Army's crossing the border. The party's origins lay in the Social Democratic and Labour Party of Bulgaria, known as the Tesni socialisti, which was founded in 1903 after a split in the Social-Democratic Party. The party's founding leader was Dimitâr Blagoev and its subsequent leaders included Georgi Dimitrov. The party opposed World War I, was sympathetic to the October Revolution in Russia and applied to join the Communist International upon its founding in 1919. Upon joining the Comintern the party was reorganised as the Communist Party of Bulgaria. Dimitrov was a member of the party's Central Committee from its inception until his death in 1949 also serving as Bulgaria's leader from 1946.

In 1938 the party merged with the Workers' Party to become the Bulgarian Workers Party. In 1948 the BWP merged with the Bulgarian Workers' Social Democratic Party to become the Bulgarian Communist Party once again.

Following Dimitrov's sudden death, the party was led by Vulko Chervenkov, a hard-line Stalinist who oversaw a number of party purges under Moscow's guidance. The party joined the Cominform at its inception in 1948 and conducted purges against suspected Titoites following the expulsion of the Communist Party of Yugoslavia from the alliance. Thousands of suspect party members and suspected counterrevolutionaries outside of the party were imprisoned. In March 1954, one year after Stalin's death, Chervenkov was deposed.

From 1954 until 1989 the party was led by Todor Zhivkov who was staunchly supportive of the Soviet Union and remained close to its leadership after Nikita Khrushchev was deposed by Leonid Brezhnev. The demands for reform which swept Eastern Europe in 1989 forced Zhivkov's resignation and the party moved in a more moderate direction, abandoning Marxism-Leninism in 1990 and renaming itself the Bulgarian Socialist Party (BSP).

A number of old Communists established several splinter parties with an insignificant number of members. One of them, the Communist Party of Bulgaria, is a BSP ally. Its leader, Alexander Paunov, is a member of the BSP-dominated Coalition for Bulgaria parliamentary faction. See also:

• Communist Bulgaria