Provided is an ultrasonic diagnostic device that performs velocity measurement in which the impact of the wavefront characteristics and scattering that accompany the propagation of shear waves is lessened. Burst waves which are first ultrasonic waves and are from a probe (11) and an ultrasonic wave transmission and reception unit (13) are transmitted to a subject and radiation pressure is imparted. The displacement of a medium within the subject that accompanies the propagation of shear waves generated in the subject by the radiation pressure is detected by transmission to the subject and reception by the subject of track pulse waves which are second ultrasonic waves. Using reception data from the ultrasonic wave transmission and reception unit (13), an elasticity evaluation unit (17) of a controller (12) measures a first arrival time of a shear wave in a first depth and a second arrival time of a shear wave in a second depth according to a single track pulse wave having a prescribed angle Ɵ (≠0) with respect to the depth direction of the subject, calculates the propagation speed of the shear wave on the basis of the difference between the first arrival time and the second arrival time, and displays the elasticity information of the subject on a display unit (15).La présente invention concerne un dispositif de diagnostic ultrasonore qui effectue une mesure de vélocité dans laquelle limpact des caractéristiques dun front donde et de la diffusion, qui accompagnent la propagation dondes de cisaillement, est atténué. Des ondes de salve, qui sont des premières ondes ultrasonores en provenance dune sonde (11) et dune unité (13) de transmission et de réception donde ultrasonore, sont transmises à un sujet et une pression de rayonnement est communiquée. Le déplacement dun support à lintérieur du sujet, qui accompagne la propagation des ondes de cisaillement générées dans le sujet par la pression de rayonnement, est détecté par transmission au sujet et réception par le sujet