An ultrasound diagnostic apparatus 1 includes a transmission section 11 which is transducer drive means capable of transmitting ultrasound at a predetermined focus position from an ultrasound transducer 2a, and a CPU 5 which is display region changing means capable of changing a display region to be displayed on a monitor 8 in an ultrasonic image and controls the transmission section 11, which is the transducer driving means, in accordance with the change result to change the focus position of the ultrasound.
