The SU-85M was an improved design (rather than a separate variant) of the SU-85 self-propelled gun used by the Soviets during World War II. It has slightly thicker frontal armour and a better commander cupola. There were 315 units built in total.

Introduced in the Closed Beta Test for Ground Forces before Update 1.41, the SU-85M should be played as a long-range sniper due to its powerful gun. Its lack of a turret makes it unsuitable for close-quarters combat, even with the thickness of its frontal armour increased compared to SU-85. Moreover, the protection gain is negligible due to the advent of more advanced enemies. It is therefore not a good idea to be close to the front lines. To increase the effectiveness of armour, players should stay behind the main fighting zone and eliminate enemy targets from far away, making the best use of long-distance and low silhouettes to enhance survivability.