When tissue elasticity of a subject is measured, an ultrasound diagnostic apparatus sets a sound velocity for each of segment regions established by dividing the subject, processes reception signals output by a piezoelectric element array based on the set sound velocities, and performs tissue elasticity measurement based on the reception signals processed based on the set sound velocities. Owing to this configuration, when tissue elasticity of a subject is measured, the ultrasound diagnostic apparatus prevents the accuracy of tissue elasticity measurement from deteriorating due to image distortions.
