Unlike the earlier Saab 21 which had been designed as a piston-engined fighter and later equipped with jets, the Saab 29 was built as a jet from the start. Designed by Lars Brising, it was notable for being the first European swept wing jet fighter to enter service although as a result of its rotund appearance was given the unflattering nickname "Tunnan" (Barrel). Still, the Saab 29 ended up being a highly effective aircraft which was later given substantial ground attack capabilities as well as retrofitted with advanced weaponry such as Sidewinder air-to-air missiles; others were used for reconnaissance. Saab 29s were the most widely produced Saab aircraft of all and only retired from Flygvapnet service until 1976, over two decades of service where they were also exported in small numbers to Austria. Interestingly, they were one of the few Swedish combat aircraft to see combat where they were used successfully in a UN peacekeeping mission in the Congo.

First flight of the prototype took place on 1 September 1948 with deliveries of the first J 29A beginning in the early 1950s. The J 29B introduced external ordinance and drop tanks while the S 29C was an unarmed reconnaissance platform. It was eventually decided to install a more powerful RM2B engine in what would become the J 29E conversion which also featured a sawtooth leading edge. Finally, the J 29F incorporated all previous enhancements as well as Sidewinder missiles and was coupled with the A 29F ground attack variant. Most of the earlier models in service were later brought up to these standards.