A method for polynomial fitting of Wassermann-Wolf surfaces and the results are presented. Conformal optics by which the missile dome is shaped to aerodynamic requirements generally introduces various kinds of aberrations as targe as tens to hundreds of wave lengths across the field of regard. Through polynomial fitting of Wassermann-Wolf surfaces and using Zernike polynomials instead of traditional merit function, the conformal optical system is implemented and an example is demonstrated. The results show that MTF of the optical system approaches to the diffraction limit across the field of view.