The Sturmgeschütz III Ausführung A (StuG III A) (Sd.Kfz. Index: Sd.Kfz. 142) is the first variant of the Sturmgeschütz III assault gun family. It was the most-produced fully tracked armoured fighting vehicle, as well as the second-most-produced German armoured combat vehicle of any type, following the Sd.Kfz. 251 half-track. It was designed on a Panzer III F chassis that had been slightly modified, with the turret removed to be replaced by an armoured, fixed superstructure holding a more powerful gun. Originally designed as a mobile assault gun for direct-fire infantry support, the overall StuG III designs were continually upgraded and, like the subsequent Jagdpanzer vehicles, were used as a tank destroyer later during World War II. While the StuG III did not see action during the battle in Poland in September 1939, the experience acquired there highlighted the importance of a self-propelled mobile artillery vehicle.

Introduced in the Closed Beta Test for Ground Forces before Update 1.41, the StuG III A serves as an infantry support vehicle, similar to the early Panzer IV variants (A to F1). Its main objective was to fire high explosive (HE) shells in an arc at enemy fortifications and defence positions with its short-barrelled 75 mm Sturmkanone (StuK) 37 L/24 tank gun. In the game, the player can hide behind low obstacles and fight enemies while in the hull-down position. This greatly improves the StuG III A's survivability to resist opposing fire. Players new to the casemate tank destroyers in the German Army ground forces may struggle to adapt to the playstyle of such vehicles, particularly the frequent requirement to shift the direction of the hull when engaging the enemy from different directions. Nonetheless, gaining skill in playing such vehicles would undoubtedly benefit the players, as most German Army casemate tank destroyers are well-armoured compared to other vehicles of their rank, while also being armed with extremely powerful guns.