PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus allowing an operator to detect the calculation state of the intersecting angle of two segments.SOLUTION: The ultrasonic diagnostic apparatus includes: an ultrasonic probe 10 transmitting/receiving ultrasonic waves to/from a subject an image structure part 14 structuring a tomographic image based on reflection echo signals received from the ultrasonic probe 10 an operation part 18 setting two segments on the tomographic image a calculation part 20 calculating the angle of the two segments on the basis of the intersecting state of the two segments and a display part 16 displaying the calculation state of the intersecting angle of the two segments.