A focal point controlling method of a focused ultrasound therapy apparatus includes receiving a plurality of focal point positions on which a focal point of an ultrasonic wave is to be formed, and receiving a sound pressure that is to be applied by the ultrasonic wave to each of the plurality of focal point positions, determining a particle velocity at each of a plurality of elements included in an ultrasound transducer, and radiating the ultrasonic wave according to the determined particle velocity. The particle velocity may be determined based on the received sound pressure that is to be applied by the ultrasonic wave to each of the plurality of focal point positions, by reflecting a sound pressure distribution of the ultrasonic wave that is generated by each of the plurality of elements.
