The invention discloses a method and system for inverting trans-space and trans-atmospheric moving target infrared radiation properties. The method comprises the following steps: firstly, determining the path type between a measurement system and an observed moving target; then, calculating parameters of infrared radiation transmission properties under the current path type; and finally carrying inversion calculation on the infrared radiation brightness of the observed moving target according to the average value of infrared radiation brightness and the parameters of the infrared radiation transmission properties of the observed moving target, which are measured for multiple times. The method and system can be used for solving the technical problem of calculating parameters of trans-space and trans-atmospheric moving-target infrared radiation transmission properties and carrying out inversion calculation of object space infrared radiation brightness.