PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus capable of estimating a degeneration degree of an articular cartilage by manually operating a probe having an ultrasonic probe from a skin surface.SOLUTION: An ultrasonic diagnostic apparatus comprises: a probe 4 that has a grip part detection means 5 of an angle of an ultrasonic wave an ultrasonic waveform data acquisition part 7 that acquires ultrasonic waveform data to be transmitted and received by the probe, with respect to each position for transmitting and receiving the ultrasonic wave, in synchronization with angle data a data processing part 8 that selects the ultrasonic waveform data of angle within a certain range from an angle of the ultrasonic wave at which a feature amount of the acquired ultrasonic waveform data becomes the largest, with respect to each position for transmitting and receiving the ultrasonic wave and a data calculation part 9 that estimates a degeneration degree of an articular cartilage by statistically processing a feature amount group of the ultrasonic waveform data for each angle within the certain range.
