A medical image diagnosis device according to an embodiment of the present invention includes: an imaging unit that takes an image of a subject, with an X-ray generation unit which exposes the subject to X-rays and an X-ray detector which detects X-rays that have passed through the subject, being supported on a supporter; a control unit that controls so as to rotate and move the supporter with respect to the subject and take images of the subject from a plurality of viewpoints; a storage unit that stores image data taken from a plurality of the viewpoints; an image processing unit that classifies a plurality of pieces of the image data stored in the storage unit into a plurality of imaging ranges to generate thumbnail images; and a display unit that displays thumbnail images generated by the image processing unit.