An image processing apparatus includes a storage unit which stores the data of a plurality of images including an examination target organ of an object, a reference point determining unit which determines, from each of the images, a reference point which is located in or near a region of the examination target organ and undergoes a relatively small displacement accompanying respiratory motion or, heartbeat, and a moving amount calculation unit which determines the position of each of a plurality of points of interest included in the region of the examination target organ relative to the reference point for each of the images, and calculates, based on the determined positions, moving amounts that corresponding points of interest between the images move accompanying the respiratory motion or the heartbeat.