Provided is an ultrasound diagnostic apparatus with which elastic modulus can be safely measured with high accuracy over a wide area when measuring elastic modulus using shear wave generation. The ultrasound diagnostic apparatus comprises: an ultrasound probe (1) that sends and receives echo signals from inside a living body； a strain-computing unit (24) that receives an echo signal from the body by radiating a first displacement-detecting beam and computes strain information in a Region 1； a measurement position-selecting unit (40) that selects a Region 2, which is contained within Region 1 and is smaller than Region 1, as the elastic modulus-measurement position on the basis of the strain information； a displacement-generating unit (10) that radiates a focused beam that is the displacement-generating transmission beam into the body and displaces the tissue； an elastic modulus-computing unit (34) that receives an echo signal from the body by radiating a second displacement-detecting beam, detects the shear wave displacement that results from the focused beam, and computes the elastic modulus in Region 2； and a display unit (7) that displays the strain image that is based on the strain information in Region 1 and the elastic modulus. The display unit (7) also displays a color scale that represents the elastic modulus in the display area of the displayed strain image.
