The Maschinengewehr 34, or MG 34, is a German air-cooled machine gun that was first produced and accepted into service in 1934, and first issued to units in 1935. It accepts the 7.92 x 57mm Mauser cartridge.

It was designed to perform both as a light machine gun and in heavier roles, as an early example of a general-purpose machine gun. In the light machine gun role, it can be equipped with a bipod and 50-round ammunition belt contained in a drum-shaped magazine attached to the receiver. In the heavier role, it is mounted on a larger tripod and is belt-fed. In practice, the infantry relied mainly on belt-cartridge ammunition for the bipod version, functioning as a classic medium support infantry weapon. The MG34 was later phased out in favour of the MG42.

The MG 34 was used as the primary infantry machine gun during the 1930s, and remained as the primary tank and aircraft defensive weapon. It was to be replaced in infantry service by the related MG42, but there were never enough quantities of the new design to go around, and MG 34s soldiered on in all roles until the end of World War II. The MG 34 was intended to replace the MG13 and other older machine guns, but these were still being used in World War II as demand was never met.