The influence of axis and radial temperature gradients on the deformation of optic window with large aperture is discussed. The optic window deformation with temperature and pressure differences on the both sides is analyzed by ansys program. Zernike polynomial, as an interface tool, connects the ansys program simulated results with the optic design program. In zemax program, the influence of optic window deformations at 12～27℃ on the optic system image quality are analyzed.