In 1969, the PLAAF issued a requirement for a small, inexpensive, STOL (short takeoff and landing) lightweight fighter to replace the MiG-19 then in service. Two designs were submitted, the Shenyang J-11 and the Nanchang J-12. Design of the J-12 was led by Lu Xiao Peng, with the prototypes being built by the Nanchang Aircraft Manufacturing Company (NAMC). Flight testing of the three prototypes began on December 26, 1970. Performance was disappointing, so additional prototypes were built with improvements such as simplified control surfaces, a lighter area ruled fuselage, and revised intake. All variants looked similar; the J-12 was a small single-seat jet fighter with a low-set swept wings, swept control surfaces, tubular fuselage, and nose intake with small or absent shock cone.
In 1977, development of the J-12 was abandoned, probably because the Chengdu J-7, based on the SovietMiG-21F, was considered superior. The J-12's main problems were insufficient firepower and engine thrust. The J-12 accumulated 61 hours in 135 flights by 1977. Nine J-12s are believed to have been built. In 1990s, Lu Xiao Peng proposed to upgrade J-12 fighter design to accommodate stealth features, and suggested modified J-12 fighter to be carrier based fighter for PLA Navy, in the none of the proposals turned into reality.