A photoacoustic device comprises a light source configured to generate first and second lights; an irradiation unit configured to generate a first acoustic wave from an object including a contrast agent by irradiating the object with the first light, and then bleach the contrast agent by irradiating the object with the second light and generate a second acoustic wave from the object by irradiating the object with the first light after bleaching; a receiving unit configured to output a first signal upon receiving the first acoustic wave and output a second signal upon receiving the second acoustic wave; and an acquisition unit configured to acquire first information based on the first signal, and acquire second information based on the second signal.