A medical image diagnostic apparatus according to an embodiment includes a compression plate, an X-ray tube, an arm, an X-ray detector, and an ultrasound probe. The compression plate compresses a breast of a subject. The X-ray tube radiates X-rays. The arm holds the X-ray tube and moves, while the X-ray tube radiating the X-rays, an irradiation region of the X-rays in a direction perpendicular to a front-rear direction of the compression plate. The X-ray detector detects the X-rays having passed through the breast of the subject. The ultrasound probe transmits and receives an ultrasound wave, the ultrasound probe being movable in the direction perpendicular to the front-rear direction of the compression plate.
