A probe includes an acoustic wave transmitting section that transmits acoustic waves toward a subject, a light irradiating section that irradiates a light beam guided from a light source, and an acoustic wave detecting section that detects photoacoustic waves generated within the subject due to irradiation of the light beam onto the subject and reflected acoustic waves of the acoustic waves transmitted into the subject. In addition, a mode switching switch is provided on the probe. A control means switches operating modes between an operating mode in which the acoustic wave detecting section detects at least photoacoustic waves, and an operating mode in which the acoustic wave detecting section does not detect photoacoustic waves.
