An ultrasound diagnostic apparatus includes the following. A deflection controller generates delay time information to make phases of reception signals input to channels uniform according to a deflection angle. A channel selector selects a channel in which the reception signal is turned on or off so that the phases of the reception signals input to channels are different and which generates channel selection information. A reception delay interrupter provides the delay amount to the reception signal and which turns on or off the reception signal. An adder adds the plurality of reception signals which are provided with the delay amount and turned on.