A probe (10) transmits and receives diagnostic ultrasound and therapeutic ultrasound. A transmission unit (12) forms a transmission beam of the therapeutic ultrasound having a higher wave number than the diagnostic ultrasound and scans the transmission beam of the therapeutic ultrasound in a therapeutic region set inside a diagnostic region by controlling the probe (10). Since the therapeutic ultrasound having a higher wave number than the diagnostic ultrasound is used, the therapeutic effect is higher than when using a therapeutic ultrasound having a similar wave number to the diagnostic ultrasound, and since the transmission beam of the therapeutic ultrasound is scanned in the therapeutic region, the therapeutic effect is higher than when the transmission beam of the therapeutic ultrasound is not scanned.
