An ultrasound diagnostic apparatus includes an ultrasound probe, a reference image holding unit that holds an ultrasound image acquired by fixing a position of the ultrasound probe as a reference image, a movement vector calculation unit that calculates a movement vector between two ultrasound images, a movement vector integration unit that integrates the movement vector from a time when the reference image is held to a current time, a deformed image generation unit that generates a deformed image in which the current ultrasound image is moved and changed to a time when the reference image is held based on an integration result, a tomographic plane determination unit that compares the deformed image with the reference image to determine whether tomographic planes of the current ultrasound image and the reference image are the same as each other, and a determination result notification unit that notifies a user of a determination result.
