The present invention provides a system and method for generating a CT slice image. The system comprises an MIP image generation module, a region of interest determination module, an angle setting module, a curve determination module, a match module and a slice generation module. The MIP image generation module generates MIP images of a reconstructed image； the region of interest determination module determines an image range in an original slice, and determines the parts of the MIP images within the image range as regions of interest； the angle setting module rotates the regions of interest to a plurality of specific angles for a plurality of times； the curve determination module generates a plurality of two-dimensional projected curves of the regions of interest for the plurality of specific angles； the match module selects a two-dimensional projected curve matching with a part to be diagnosed based on features of the plurality of two-dimensional projected curves； the slice generation module determines a slice position range and a slice angle based on the features of the matched curve and the corresponding specific angle.
