On the operation of high-speed flight, a large amount of heat is produced due to the friction between the optical window glass and the atmosphere, by which the optical window glass deforms. Then, as light pass though the deformed window, problems as bending and difference of optical path are presented, which affect the optical system imaging of aerial remote sensor. In order to restrain the influence, the structure of the double optical window is investigated, and the optical performance of the monolayer and double optical window is analyzed. According to the window structure, methods determining the thickness of circular and rectangular window are provided on the outside working environment as well as the influence of different window installation of thickness. The deformation of optical window on the influence of pressure and temperature is analyzed, and thermal deformation analysis of the double window is also investigated combined with the flight condition. The optical property of double window is verified and compared with the equivalent thickness of the monolayer window. Analysis results show that under the condition of airborne remote sensing device speed, the radial temperature difference and axial temperature difference of double window glass are smaller than those of the monolayer window with the same thickness. For the studied optical system, the coke quantity of double optical window glass caused by hot deformation is smaller and the effect to the modulation transfer function (MTF) of optical system is weaker. The influence of the spatial frequency ranging from 0 to 65 cycle/mm is no less than 0.3 and the relative decline of MTF is no more than 10% with spatial frequency 65 cycle/mm. The optical system of the double optical window can satisfy the use requirement in the case of without focusing. The analysis study of double optical window can be referenced in the domain of designing the optical window of aerial remote sensor.