"On the Cult of Personality and Its Consequences" was a report by Soviet leader Nikita Khrushchev, First Secretary of the Communist Party of the Soviet Union, made to the 20th Congress of the Communist Party of the Soviet Union on 25 February 1956. Khrushchev's speech was sharply critical of the rule of the deceased General Secretary and Premier Joseph Stalin, particularly with respect to the purges which had especially marked the last years of the 1930s. Khrushchev charged Stalin with having fostered a leadership cult of personality despite ostensibly maintaining support for the ideals of communism. The speech was leaked to the West by the Israeli intelligence agency Shin Bet, which received it from the Polish-Jewish journalist Wiktor Grajewski.

The speech was shocking in its day. There are reports that the audience reacted with applause and laughter at several points. There are also reports that some of those present suffered heart attacks and others later took their own lives due to shock at the revelations of Stalin's use of terror. The ensuing confusion among many Soviet citizens, raised on panegyrics and permanent praise of the "genius" of Stalin, was especially apparent in Georgia, Stalin's homeland, where the days of protests and rioting ended with the Soviet army crackdown on 9 March 1956. In the West, the speech politically devastated organised communists; the Communist Party USA alone lost more than 30,000 members within weeks of its publication.

The speech was cited as a major cause of the Sino-Soviet split by China (under Chairman Mao Zedong) and Albania (under First Secretary Enver Hoxha) who condemned Khrushchev as a revisionist. In response, they formed the anti-revisionist movement, criticizing the post-Stalin leadership of the Communist Party of the Soviet Union for allegedly deviating from the path of Lenin and Stalin. Mao strengthened his own cult of personality equivalent to Stalin. In North Korea, factions of the Workers' Party of Korea attempt to remove Chairman Kim Il-sung by criticizing him for not "correcting" his leadership methods, developing a personality cult, distorting the "Leninist principle of collective leadership" and "distortions of socialist legality" (i.e. using arbitrary arrest and executions) and use other Khrushchev-era criticisms of Stalinism against Kim Il-sung's leadership. The attempt to remove Kim failed and the participants were arrested and later executed, allowing Kim to further strengthen his own cult of personality as well. The speech was a milestone in the Khrushchev Thaw. It possibly served Khrushchev's ulterior motives to legitimize and consolidate his control of the Soviet Union's party and government after political struggles with Georgy Malenkov and firm Stalin loyalists such as Vyacheslav Molotov, who were involved to varying degrees in the purges.