In the Soviet Union, a military district (Russian: вое́нный о́круг, voyenny okrug) was a territorial association of military units, formations, military schools, and various local military administrative establishments known as military commissariats. This territorial division type was utilised in the USSR to provide a more efficient management of army units, their training and other operations activities related to combat readiness.

First military districts in the USSR begun with the formation of the first six military districts (Yaroslavsky, Moskovsky, Orlovsky, Belomorsky, Uralsky, and Privolzhsky) on 31 March 1918 during the Russian Civil War to prepare substantial army reserves for the front.

The next reform did not take place until the economic reforms (NEP) of 1923 which concluded in 1929. At this time the military districts in the Russian Soviet Republic still conformed to the gubernyas and oblasts of the Russian Empire, with the exception of the other republics each of which constituted a military district in their own right.

Abbreviation of 17 military districts of the USSR at the beginning July 1940:

Formations in the territory of Khabarovsk and Primorsky Krai were combined into the 1st and 2nd independent Red Banner Armieswhich, after January 14, 1941, were reformed into the Far Eastern Front.

The number of military districts varied depending on the circumstances and with the evolution of the Soviet Army. Before the eastern campaign of 1941–45, there were 16 military districts and one front although this number fluctuated and as many as 25 military districts existed at different time before the war.

North and North Western districts

West and Central USSR districts