Abstract: It is always a difficult problem to analyze the infrared radiation of space target. Sinda/G and Matlab were advanced to analyze the infrared radiation of space target. Firstly, the working principle of Sinda/G was introduced and the method used to analyze the infrared radiation of space target was explained in detail. In order to analyze the usefulness of the method in detail, Sinda/G and Matlab were used to analyze the infrared radiation intensity emitted from a spherical shell target. Besides, the infrared radiation intensity accepted by the detector was emulated both in different time and in different directions. The emulation results show that the method is of great significance to analyze the infrared radiation of the space target, to detect and track the space target.