The invention discloses a method for simulating an infrared small target image sequence based on a mean value model. The method comprises the following specific steps: (1), acquiring the background of an image; (2), simulating the background of a target image; (3), expanding a mirror image; (4), establishing a target model; (5), setting a target track; (6), synthesizing the target image; (7), accumulating 1 to the number i of a background frame of a simulated infrared small target image; (8), judging whether the number of the background frame of the simulated infrared small target image added with 1 is equal to the total frame number L of a simulated infrared small target image sequence or not, if so, performing a step (9), and if not, performing the step (2); and (9), outputting the simulated infrared small target image sequence. The method disclosed by the invention has the advantages that: the calculation amount is low; the validity of the simulated infrared small target image is high; texture detail characteristics are enriched; and furthermore, the size, the signal-to-noise ratio, the motion speed and the track of an infrared small target are controllable.