An apparatus processes a medical image. A three-dimensional data acquisition unit acquires three-dimensional data of a plurality of objects for diagnosis of a living body. A three-dimensional data memory stores the three-dimensional data of each of the plurality of objects for diagnosis. A sectional position memory stores a plurality of sectional positions for each of the plurality of objects for diagnosis. A selector selects one of the plurality of objects for diagnosis. An image generation unit generates a plurality of sectional images using the three-dimensional data corresponding to the one of the plurality of objects for diagnosis. Each image is along a different sectional position in the one of the plurality of objects for diagnosis.