The invention relates to an anti-infrared-detection system and a preparation method thereof. The anti-infrared-detection system comprises a heat insulation layer embedded in a target skin and a heat exchanger laid outside the target skin, wherein the heat exchanger is composed of a plurality of heat exchange modules arranged side by side, each heat exchange module is composed of a plurality of heat exchange units arranged side by side, each heat exchange unit comprises a phase change material, and the phase change materials of the plurality of heat exchange units in each heat exchange module are different from one another. The system has the advantages of simple structure, safety, reliability, strong adaptability and good camouflage effect, and can effectively reduce the probability that atarget is detected and struck by infrared reconnaissance, and the preparation method has the advantages of simple process, easy realization and convenient operation.