DOSAAF (Russian: ДОСААФ), full name Volunteer Society for the Assistance to the Army, Aviation, and Navy (Russian: Добровольное общество содействия армии, авиации и флоту, romanized: Dobrovol'noe obshchestvo sodeystviya armii, aviatsii i flotu), was a paramilitary sport organization in the Soviet Union, concerned mainly with weapons, automobiles and aviation.

The stated goal of the society was "patriotic upbringing of the population and preparation of it to the defense of the Motherland".

The precursor of DOSAAF was the OSOAVIAKhIM (Russian: ОСОАВИАХИМ; full name: Союз обществ содействия обороне и авиационно-химическому строительству СССР, 'Union of Societies of Assistance to Defense and Aviation-Chemical Construction of the USSR') created on 27 January 1927 by merging the Society of Assistance to Defense (Общество содействия обороне (ОСО)), Society of Friends of the Air Force (Общество друзей Воздушного флота (ОДВФ)) and Society of Friends of Chemical Defense and the Chemical Industry (Общество друзей химической обороны и химической промышленности (Доброхим СССР)).

OSOAVIAKhIM supported a number of professional research and development programs for airplanes, glider, airships and stratospheric balloons, some of which were later taken over by the Soviet Air Forces.

Also in the 1930s, Sergey Korolev's rocket research organization, GIRD, and Oleg Antonov's glider project, among other efforts, were part of the OSOAVIAKhIM.