1. A medical image processing system comprising: an angio-image obtaining unit for obtaining a required angio-image from multiple chronological angio-images; an angio-image imaging direction obtaining unit for obtaining a direction of imaging as incidental information included in data on the required angio-image; a CT-image obtaining unit for obtaining a three-dimensional CT-image corresponding to the required angio-image; a blood vessel part extracting unit for extracting a blood vessel part in the three-dimensional CT-image; a projected image generating unit for generating a three-dimensional projected image by projecting the blood vessel part, and for generating a three-dimensional projected image corresponding to a direction of a projection after a manual operation operates the direction of the projection; and a display control unit for making display the three-dimensional projected image and the angio-image.