A medical image diagnostic apparatus according to an embodiment includes image generation circuitry, a touch panel, and control circuitry. The image generation circuitry generates a medical image based on data collected through scanning on a subject. The touch panel displays the medical image, and detects a tap operation, a long-press operation, or a flick operation on the displayed medical image. The control circuitry changes a parameter that affects the display of the medical image in a region relative to a position where the tap operation, the long-press operation, or the flick operation is detected, based on at least one of the strength of the tap operation, the number of times of the tap operation, the strength of the long-press operation, the long-press time of the long-press operation, the strength of the flick operation, the direction of the flick operation, and the speed of the flick operation.