An ultrasonic diagnostic device includes: a probe including a plurality of elements that generate and transmit ultrasonic waves and receive ultrasonic waves reflected from a subject; a transmission unit that transmits ultrasonic beams toward the subject from the plurality of elements of the probe; an image generation unit that generates an ultrasonic image by performing reception focusing for reception signals obtained by receiving the ultrasonic waves reflected from the subject in the plurality of elements of the probe; and a control unit that, when performing reception focusing in a direction different from a normal direction of each of the elements that form a reception opening of the probe, controls the image generation unit to generate an ultrasonic image in a direction different from the normal direction using only a signal having a predetermined low frequency band among the reception signals.