An object of the present invention is to provide an ultrasound diagnostic device being able to display an ultrasound image which is not limited to a region targeted for ultrasound emission. The ultrasound diagnostic device is provided with an ultrasound probe having an ultrasound emitting surface for emitting an ultrasound wave and receiving a reflected wave of the ultrasound wave, an ultrasound image generator for generating an ultrasound image by using an reflected echo signal based on the reflected wave, an ultrasound volume data generator for accumulating the ultrasound images to generate three-dimensional ultrasound volume data of a test object, a reference image generator for generating multiple reference images by using three-dimensional volume data and the ultrasound volume data, and a display unit for displaying the ultrasound image and the reference images.
