A coaxial alignment method of zoom system based on aberration feature analysis was proposed. Aiming at the alignment for a certain type of 20 times zoom optical system, the coaxiality of the optical elements in each lens group of the zoom system was improved by using the optical centering processing technology on the basis of analyzing the alignment requirements of the zoom optical system. The Zygo interferometer was used to detect the aberration feature distribution of the zoom system in the long and short focal positions. With the help of CodeV software, the tolerance sensitivity distribution of each optical element in the system was simulated to determine the sensitive optical elements which generated aberration effect. The final imaging quality of the optical system was adjusted on the center deviation measuring instrument. In addition, a coaxiality debugging device of the zoom optical system was designed to precisely measure the parallelism between the axis of the mechanical inner hole of the zoom camera main lens barrel and the linear guideway, so as to ensure the coaxial accuracy of the optical axis of the moving group. The results show that the imaging quality of the zoom system is obviously improved and the consistency of the image plane is guaranteed. The transfer function value of the long and short focal axes is better than the technical requirement value 0.45 and 0.55 respectively, and the transfer function value of the external long and short focal axes 0.7 field of view is superior to the technical requirement value of 0.25 and 0.35 respectively, which realizes the high-precision alignment and verifies the reliability of the method.