Disclosed is a technology that prevents a part of a touch panel-equipped display displaying an ultrasonic tomographic image from getting dirty with a fingerprint or scratch when using a drag operation to change the content of the ultrasonic tomographic image displayed on the touch panel-equipped display. According to this technology, the display screen is divided into an ultrasonic image area A1 which displays an ultrasonic image P and an operating part display area A2 which displays buttons (Fov, Pos, ROI, and Dop) for selecting a change to be made in the ultrasonic image P. The operating part display area A2 has a touch panel, and when a finger F selectively touches one of the displayed buttons and is dragged, the displayed image P of the ultrasonic image area A1 is changed on the apparatus side according to the selected changes and drag direction.