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.
