An ultrasound diagnostic apparatus includes a probe having an array transducer, a transmitting unit that transmits an ultrasound beam from the array transducer, an insertion device insertable into a subject and having a photoacoustic wave generation unit, a light source that irradiates the photoacoustic wave generation unit with light to generate a photoacoustic wave, a sequence control unit that performs control so that a photoacoustic wave is received each time the array transducer receives an ultrasound echo along a predetermined number of scan lines, an insertion depth detection unit that detects an insertion depth of the insertion device on the basis of a photoacoustic wave reception signal, and a notification unit that provides a notification to a user in a case where the insertion depth of the insertion device is deeper than a determined depth.