The present application provides a method and system for acquiring centerline of aorta based on CT sequence images. The method comprises: acquiring three-dimensional data of CT sequence images; acquiring a gravity center of heart and a gravity center of spine based on the three-dimensional data; filtering impurity data from the three-dimensional data of CT sequence images to obtain an image containing left atrium, left ventricle and without interfering coronary artery tree; layered slicing to obtain a group of binarized images; obtaining a circle center and an radius from each layer of slice in the group of binarized images, to generate a point list and an radius list; and mapping one or more pixel points in the point list and the radius list to the image to obtain a centerline of aorta.