Vyacheslav Rudolfovich Menzhinsky (Russian: Вячесла́в Рудо́льфович Менжи́нский, Polish: Wiesław Rudolfowicz Mężyński; 31 August [O.S. 19 August] 1874 – 10 May 1934) was a Soviet revolutionary and politician who served as chairman of the OGPU, the secret police of the Soviet Union, from 1926 to 1934.

Born to Polish parents in Saint Petersburg, Menzhinsky joined the Russian Social Democratic Labour Party in 1902. He emigrated from Russia in 1907, and spent the next decade in Europe and the United States. After the 1917 February Revolution, he joined the Cheka in 1919, and in 1923 was promoted to its deputy under Felix Dzerzhinsky. After his death in 1926, Menzhinsky became head of the Cheka's successor, the OGPU. He worked to crush resistance in the countryside during Joseph Stalin's forced agricultural collectivization.