The first Battle of Smolensk (German: Kesselschlacht bei Smolensk, lit. 'Cauldron-battle at Smolensk'; Russian: Смоленская стратегическая оборонительная операция, romanized: Smolenskaya strategicheskaya oboronitelnaya operatsiya, lit. 'Smolensk strategic defensive operation') was a battle during the second phase of Operation Barbarossa, the Axis invasion of the Soviet Union, in World War II. It was fought around the city of Smolensk between 10 July and 10 September 1941, about 400 km (250 mi) west of Moscow. The Ostheer had advanced 500 km (310 mi) into the USSR in the 18 days after the invasion on 22 June 1941.

The Soviet 16th, 19th and the 20th armies were encircled and destroyed just to the east of Smolensk, though many of the men from the 19th and 20th armies managed to escape the pocket. Some historians have asserted that the cost to the Germans during this drawn-out battle and the delay in the drive towards Moscow led to the victory of the Red Army in the Battle of Moscow of December 1941.