The impact of the high-temperature phase change material on conventional infrared decoy’s combustion performance and infrared radiation characteristics was studied. The selected high-temperature phase change materials did not reduce infrared radiation in the 3～5 μm or 8～14 μm band of infrared decoy, while extended the burning time, and reduced the burning rate of the grain, thus prolonged the effective interference time of IR decoy. The results show the phase change material is effective infrared decoy functional additives.