An ultrasonic diagnostic apparatus is used to obtain ultrasonic tomography images of subjects under examination. The ultrasonic diagnostic apparatus of the present invention comprises an ultrasonic probe consisting of an array of transducer elements for transmitting and receiving ultrasonic waves, driving means for producing driving signals to excite said transducer elements so that a transmitting beam is transmitted from the ultrasonic probe in a predetermined direction, receiving means for receiving ultrasonic reflected waves from within a subject under examination which form a receiving waves from a predetermined direction of reception by a predetermined number of elements of the plurality of transducer elements and outputting a receive signal, ultrasonic beam direction control means for controlling the driving signals and the receive signal so that the transmitting beam and the receiving waves cross each other within a predetermined region within the subject and the region where the transmitting beam and the receiving waves cross each other is shifted along the direction of the transmitting beam with time, and display means for displaying ultrasonic reflected waves received by the receiving means as an image.