The Mikoyan-Gurevich MiG-3 (Russian: Микоян и Гуревич МиГ-3) was a Soviet fighter and interceptor aircraft used during World War II. It was a development of the MiG-1 by the OKO (opytno-konstruktorskij otdel — Experimental Design Department) of Zavod (Factory) No. 1 to remedy problems 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.