An ultrasound diagnostic apparatus includes an ultrasound probe, a location sensor that detects a location of the ultrasound probe, and a location calculation device configured to calculate a location of echo data in a first three-dimensional coordinate system having a certain point as an origin based on the probe location. A deformation calculation device performs a deformation calculation to deform a shape of the body tissue in either an ultrasound image or a medical image captured by a medical imaging apparatus other than the ultrasound diagnostic apparatus to a shape of the body tissue of the other image. A display image control device performs a coordinate conversion between the coordinate system of the ultrasound image and a coordinate system of the medical image and displays a deformed image based on the deformation calculation and the other image about a same cross-section on a display device.
