The existence of the deviation error of the lens center in the transmissive optical system affects the coaxiality of the optical system, resulting in eccentric aberration and affecting the imaging quality. The application of aspheric lens can reduce the aberration of the optical system, and it is more and more widely used. In order to study the difference of the decentering aberration of the system caused by the decentering error of the aspheric lens and the spherical lens, a method for analyzing the central eccentric error of optical system by optimal optical axis fitting is proposed.?Combined with Seidel polynomials, the misalignment parameters are added to the system by Zemax software, and the difference of the influence of the same center deviation error on the aberration of spherical and aspherical systems is derived. Experimental results show that the aberration of the optical system caused by the deviation of the center of the aspheric lens is relatively large. Compared with spherical lenses, in the processing and manufacturing process of aspheric lenses, the center deviation error must be more strictly controlled.