The constitution and working principle of IR capturing and tracking equipment are described． The key technologies limiting the simulation system are analyzed．Aiming at the simulation accuracy，the method that simulates the target’s location is put forward by collecting the data from the coders directly．As for the real-time requirement of IR image generation，corresponding method that generates the images of targets and background in advance and synthesizes them real-time are proposed．The validity and feasibility of the solutions are validated through simulation． Finally，some advice is given to design the simulation system．