The target infrared radiation characteristics are analyzed. Parameters of equivalent infrared signal source in the field are calculated, and construction of infrared target simulation system in the field is described. The main parameters of the system are confirmed according to the analysis and calculation of equivalent infrared signal source parameters in the field. The composition and operation principle of the system are introduced. The research results show that the target characteristics of the system in the field are fully showed, which can be an important method for performance test of infrared system in the field.