Grigori Petrovitch Maximoff (Russian: Григо́рий Петро́вич Макси́мов; November 10, 1893, Smolensk Oblast–March 16, 1950, Chicago) was a Russian-born anarcho-syndicalist who was involved in Nabat, a Ukrainian anarcho-syndicalist movement. Along with several other anarchists, he was imprisoned on 8 March 1921 following a Cheka sweep of anarchists in the area. After a hunger strike attracted the attention of visiting syndicalists, Maximoff was one of the 10 anarchists who were released from prison and deported.
Maximoff's work was first published in the US by the Union of Russian Workers, an anarchist organization with nearly 10,000 members which had a substantial presence in New York City.
Maximoff is best remembered for his book entitled The Guillotine at Work: Twenty Years of Terror in Russia about Bolshevik repression of anarchists and syndicalists after the Russian Revolution of 1917.