The M109G was a German modification of the American M109 self-propelled howitzer. Between 1964 and 1972, Bundeswehr purchased 586 M109 SPGs in two batches, which Rheinmetall significantly modified. One of the key changes was an improved breech and muzzle brake, which increased the maximum firing range and simplified operation. The vehicle also received German-made tracks, a fire control system, and an engine. Starting in 1966, M109G vehicles were equipped with a smoke grenade launchers and a new commander’s cupola with an MG3 machine gun. In this configuration, the vehicles remained in service with the Bundeswehr until 1990. Afterward, the remaining M109G units were upgraded to the American M109A3G standard.

The M109G was introduced in Update 2.31 "Kings of Battle". Its 155mm gun can destroy even the most heavily armored enemy tanks with a single accurate shot. Its primary ammunition consists of powerful high-explosive shells. The presence of a proximity fuse allows the M109G to engage aircraft as well. Additionally, the M109G has fairly good mobility, enabling it to keep pace with other medium tanks. However, like most self-propelled artillery, the M109G's armor only reliably protects against machine gun fire and shell fragments. The large crew makes it possible to survive several non-critical hits. The vehicle also has a slow reload speed.