Abstract: An ultrasonic diagnostic apparatus which displays a two-dimensional sectional image of, for example, the left ventricle of the heart by sending and receiving ultrasonic waves. A reference point is set in the left ventricle, and an outline of the left ventricle is identified using this point. The left ventricle is radially divided from the reference point into plural division regions, e.g. four regions. The area of each division region is calculated at each point in time, and an area variation rate is computed from the ratio of the area and a reference area. The area variation rate for each division region is continuously displayed as a graph. On this graph, a part with dull motion (diseased part) can easily be identified.