To provide an ultrasonic diagnostic instrument for automatically selecting a display image by kinds of ultrasonic probes, and also to freely select a display image other than the automatically selected image.

The instrument transmits/receives ultrasonic waves with the ultrasonic probe, and displays the ultrasonic image of a subject, on the basis of acquired echo data. The instrument includes: an identifying means for identifying the kind of the connected ultrasonic probe; and an input/output setting means for arithmetically processing echo data and organizing display image data in order to display the optimum display image in accordance with the kind of the ultrasonic probe which is identified by the identifying means.