The First Secretary of the Mari regional branch of the Communist Party of the Soviet Union was the position of highest authority in the Mari AO (1920–1936) and the Mari ASSR (1936–1991) in the Russian SFSR of the Soviet Union. The position was created on February 24, 1921, and abolished on August 25, 1991. The First Secretary was a de facto appointed position usually by the Politburo or the General Secretary himself.