The performance of an infrared imaging system is affected by spatial fixed-pattern noise badly due to the different photoresponse of each detector in a focal plane array for the same irradiance. A novel nonuniformity correction algorithm based on Wiener filtering is developed, which first determines an output delay for being able to use the later information of an uncorrected image, and then by depending on the front and back information of a current frame, Wiener filter is adopted to estimate the current frame for several times. At last, take the average value of the estimations as the final correction result. The performance of the proposed algorithm is demonstrated with a real infrared image, and its advantage is that it can employ sufficient information to eliminate the fixed-pattern noise.