The invention discloses a photoacoustic apparatus and subject information acquisition method. The photoacoustic apparatus includes a light irradiation unit configured to irradiate a subject with pulsed light a plurality of times, a reception unit configured to receive photoacoustic waves generated by the plurality of times of irradiation of the subject with the pulsed light from the light irradiation unit, and output a plurality of signals corresponding to the plurality of times of light irradiation, a blood information acquisition unit configured to acquire information on an amount of blood of the subject, and a subject information acquisition unit configured to acquire subject information of a target region in the subject based on the plurality of signals, wherein the subject information acquisition unit acquires the subject information based on a plurality of signals acquired in a common period in each of repeated cycles of fluctuation of the amount of blood.