An ultrasonic imaging device according to the present invention includes: a container provided with an opening for inserting a target region of a subject and a transmission/reception unit that transmits ultrasound to the target region inserted into the container filled with a liquid and receives the ultrasound that penetrates the target region or is reflected from the target region. The container has a pressure reducing unit that holds the target region in the container by reducing a pressure in the container of which the opening is covered with the target region. According to the present invention, since it is possible to maintain a shape close to a predetermined shape when the target region of a breast or the like is inserted into a container filled with the liquid, it is possible to measure the target region with high accuracy by transmitting and receiving ultrasound.
