Abstract: In view of the urgent need for domestic decoys loop simulation technology and infrared guidance technology research, a finite element modeling method interference characteristics for decoys was proposed in this paper. The mechanism and the operating status of the decoys were analyzed, the flow field of the decoys were solved accurately based on finite element theory. Then the changes of air resistance in the process of decoys sports movement and the distribution of temperature field were studied in the paper, and the decoys movement characteristics and radiative properties of the finite element model were set up, which provides a theoretical basis for the hardware-in-loop simulation. And simulation verify the validity and correctness of the proposed model. The method can not only provide the basis for the infrared decoys design and infrared-guided algorithm research, but also have important guiding significance of infrared decoy HIL simulation system.