Abstract: In this study, we propose an automatic segmentation method of aorta and heart in Computed Tomography Angiography (CTA) using Hough transform and edge map. First, we smooth the images by applying anisotropic diffusion filter to remove noise. Second, the Volume of Interest (VOI) is detected by using k-means clustering and edge map. Third, we detect the beginning of aorta using Hough transform. Finally, we extract the left and right heart with separating energy function which we proposed to split the heart. We tested our method in ten CT images and they were obtained from a different patient.