An ultrasound diagnostic apparatus according to an embodiment includes transmitting and receiving circuitry, adding circuitry, and image generating circuitry, and control circuitry. The transmitting and receiving circuitry performs, more than once on the same scan line, an ultrasound transmission and reception repeatedly performed with phase polarities being inverted on the same scan line, according to a number set as a scan condition parameter. The adding circuitry adds together reflected wave data received as a result of the ultrasound transmission and receptions. The image generating circuitry generates an image by using the reflected wave data that have been added together. The control circuitry controls the transmitting and receiving circuitry, based on a relation between the number of the ultrasound transmission and receptions and a scan condition parameter other than the number.
