Ambient temperature is one of the main factors affecting the imaging quality of aspheric optical systems. The analysis method of thermal optical properties was used to analyze the thermal optical properties of an airborne camera aspheric optical system. The finite element method was used to analyze the thermal deformation of the camera optical system structure, and the rigid body displacement of the mirror surface was removed. The surface data was input into the optical software program for Zernike polynomial fitting, and the fitting results were imported into the optical design software to evaluate the imaging performance of aspheric optical system. The results show that the analysis method of thermal optical properties can effectively simulate the practical working environment of the aspheric optical system, and predict the influence of ambient temperature on the imaging quality of optical system, which have guiding significance for the optical system design.