Infrared focal plane arrays ( IRFPA) imaging system performance is seriously limited by the inherent nonuniformity of IRFPA , so the nonuniformity is one of the key porblems need to be solved in the IRFPA applications. The forming mechanism and the correction principle of the nonuniformity are presented in the paper. Then the emulation experimental results ofnonuniformity correction are given.nonuniformity of IRFPA , so the nonuniformity is one of the key porblems need to be solved in the IRFPA applications. The forming mechanism and the correction principle of the nonuniformity are presented in the paper. Then the emulation experimental results of nonuniformity correction are given.