The infrared radiation characteristics of the plume of stealth aircraft are the key radiation resource for stealth aircraft detection. A new model was presented to calculate the infrared radiation of a stealth aircraft. Based on the model of the normal aircraft, the new model introduced the infrared radiation suppression module to describe the effect of infrared suppression technology. In order to test the feasibility of the model, for the lake of data, the new model was applied to calculate the infrared radiation of plume of the normal aircraft and stealth aircraft. The new model considered the impact of the 2D-nozzle plume, ejection, infrared obscure cloud and blocking on plume radiation of stealth aircraft. The calculation results show that plume radiation add stealth measures is the 5.8% of not added. Compared the calculation results with the reference results and tested spectrum data of the combustion of the aviation kerosene, it was found that the magnitude change in radiation energy is the same as the references, so the new model can be used for calculating infrared radiation of the plume of stealth aircraft.