A medical image diagnostic apparatus includes an acquisition circuitry configured to acquire data concerning the interior of an object, a reconstruction circuitry configured to reconstruct the first image concerning the object based on the acquired data, a display, and an enlargement reconstruction circuitry configured to enlarge/reconstruct the second image corresponding to the set enlargement reconstruction range based on a portion of the acquired data, with the second image being displayed in a display area of the display in place of a portion of the first image under the control of the display control circuitry.