The Pak 38 was first used by the German forces during the Second World War in April 1941. When the Germans faced Soviet tanks in 1941 during Operation Barbarossa, the Pak 38 was one of the few early guns capable of penetrating the 45 mm (1.8 in) sloped armor of the T-34's hull at close range.
The gun was also equipped with Panzergranate 40 APCR shots with a hard tungsten core, in an attempt to penetrate the armor of the heavier KV-1 tank.
Although it was replaced by more powerful weapons, it remained a useful weapon and remained in service with the Wehrmacht until the end of the war.
The Pak 38 carriage was also used for the 7.5 cm Pak 97/38 and the 7.5 cm Pak 50 guns.