Semyon Konstantinovich Timoshenko (Russian: Семён Константи́нович Тимоше́нко, Semën Konstantinovič Timošenko; Ukrainian: Семе́н Костянти́нович Тимоше́нко, Semen Kostiantynovych Tymoshenko) (18 February [O.S. 6 February] 1895 – 31 March 1970) was a Soviet military commander and senior professional officer of the Red Army at the beginning of the Soviet invasion of Poland in 1939.