In early 1942, the design team at Zavod #38 in Kirow began its development of a self-propelled gun based upon the T-60 chassis, specified as OSU-76 (Opytnaya Samokhodnaya Ustanovka). The OSU-76 was armed with a 76.2mm ZiS-3 gun mounted on the rear of a modified T-60 light tank. Inadequate size of the chassis resulted in the T-60 chassis being replaced with a T-70 chassis and a new project. In the spring of 1942, the Grabin team at Zavod #92 in Gorki designed the SU-12. This was practically an enlarged chassis with a 76.2mm ZiS-3 gun in an open-top superstructure at the rear. After completed trials in the summer of 1942, the GKO accepted it for production, known as the SU-76 light mechanized gun. The new vehicle was intended to provide fire support for rifle and tank units, and eventually to act as a tank destroyer. A total of 26 SU-76 were built during 1942. Engine system proved to be very unreliable on early vehicles and in the spring of 1943 design responsibility shifted to Astrov's Bureau and later a modified vehicle appeared, known as SU-76M. The forward hull was redesigned and minor improvements were made to the rear casemate. The SU-76M immediately entered production at GAZ and Zavod #38. GAZ was the main supplier of SU-76M and eventually Zavod #40 in Mtishchi outside Moscow became involved in the production of SU-76M. The open rear made the SU-76M a pain to serve in during harsh weather conditions, and the crew were very vulnerable to small arms and grenades. It was nicknamed "Suka" after the acronym SU (pronounced "soo") which is Russian for "bitch". With the driver situated directly next to the engines without a bulkhead driving for any longer time was a pain in the summer. In 1943, Astrov's team developed the SU-76B in an attempt to solve all the complaints about the lack of overhead armor protection. The extra weight affected performance, and it was not accepted for service.

In 1944, very few SU-76M were refitted with a single 37mm anti-aircraft gun and was specified as ZSU-37-1. A twin-barrelled version with two 37mm guns was specified as ZSU-37-2. 70 ZSU was built in 1944, and when production ceased in 1948 some 340 vehicles had been built.

Some 190 captured German StuG III assault guns got a new superstructure mounting the Russian 76mm ZiS-3 gun. These were designated SU-76i.

A total of 12.671 SU-76/SU-76Ms were manufactured, and it was the second most common armored vehicle in the Red Army. The SU-76M were used by many nations until the mid -80s.