The Mikoyan-Gurevich MiG-3 was a Soviet fighter aircraft used during World War II. It was a development of the MiG-1 by the OKO of Zavod (Factory) No. 1 to remedy problems that had been found during the MiG-1's development and operations. It replaced the MiG-1 on the production line at Factory No. 1 on 20 December 1940 and was built in large numbers during 1941 before Factory No. 1 was converted to build the Ilyushin Il-2.
By mid 1941, the MiG fighter was being introduced to the Soviet Air Force, slowly replacing the Polikarpov biplane fighters and their monoplane cousins. However, compared with the huge quantity of 109's, their impact was little felt.