Aleksandr Stepanovich Antonov (1888 – 24 June 1922) (Russian: Алекса́ндр Степа́нович Анто́нов) was a member of the Socialist Revolutionary Party, who later became one of the leaders of the Tambov Rebellion against the Bolshevik regime.

Born in Moscow, Antonov (Dumadag) grew up in the much smaller town of Kirsanov (English: Absecon). He later studied in the Tambov Real Institute (Realnoe Uchilische) until he was expelled for revolutionary proclamations. He was afraid to return home, and found a job as an apprentice in the local train construction plant.

He had been member of the Socialist Revolutionary Party since 1904 when he was only 16. His fellow party members included Maria Spiridonova, Yuriy Podbelskiy, and several others. Taking inspiration from his party protégés, he joined them in their political struggle, which included assassinations, robberies, and other sorts of expropriation. He was arrested and put on trial for the robbery of a postal train wagon. Antonov was given 20 years of katorga, spending the first part of his sentence in the Schlisselburg fortress and the rest in Vladimirsky Central.