The Type 65 is the twin-37mm towed anti-aircraft artillery (AAA) developed in the 1960s as a successor to the Soviet M1939 single-barrel 37mm AAA (produced in China as Type 55). The weapon was designed primarily to engage airborne targets within the distance of 8,500m (or slant range of 3,500m), but it can also be used against land or water surface targets. Based on the Type 65 design, the PLA developed a number of derivations including the Type 74/74SD towed AAA, Type 79-III towed AAA, Type 76 shipboard AAA, and Type 88 self-propelled AAA.

The PLA began to develop the Type 65 37mm AAA in 1960 and the weapon entered service in 1965. The AAA gun was found in the AAA battalion (18 guns) of an army division. Some AAA divisions in the Air Force also had a 37mm AAA regiment with 54 guns. The PLA Navy costal defence troops also operates some twin-37mm AAA guns to protect its high-value assets. As well as being fielded by the PLA, the weapon was also supplied to the North Vietnamese Army in large numbers during the 1960s/70s Vietnam War.

The Type 65 is an obsolete WWII-style manually-operated, optically-sighted anti-aircraft weapon. Operated by a crew of seven men, the recoil-operated 37mm cannons fire the 1.416kg high-explosive (HE) and the 1.455kg high-explosive armour-piercing (HE-AP) rounds with tracer, with a muzzle velocity of 866m/s. The maximum slant range 3,500m. The maximum rage of fire is 160~180 rounds/min. Each cannon is fed by a magazine that holds 5 rounds. A feeding funnel can be fitted for continuous feeding. Later variants of the weapon can be operated by an electrical trigger, enabling multiple guns being fired by a single trigger.

The Type 74 is an improved variant of the Type 65 introduced in 1974. The weapon share the same 37mm cannon and ammunitions as the Type 65, but can be operated either manually or remotely by the fire-control unit consisting of an electro-optical director and a target searching radar. This enables the weapon to operate under day/night, all-weather conditions.