Abstract: A nonuniformity correction algorithm based on image decomposition of nonuniformity in IRFPA was proposed, for the engineering application limitations of traditional adaptive nonuniformity for IRFPA. After analysis of the constructing factor of nonuniformity, the algorithm decomposes the high-frequency part of nonuniformity into bright pixels, row and column nonunniformity, and the low-frequency part of nonuniformity into gradient nonunifority, and then corrects every kind of nonunifority using a special algorithm, and completes the correction by combination. The algorithm was tested in a infrared imaging system and compared with other adaptive non-uniformity correction algorithms. According to the analysis of simulation results, this algorithm has the advantage of strong ability to eliminate the target fade-out, fast convergence speed and high precision.