A photoacoustic apparatus, comprises a light source that irradiates an object with light； a plurality of acoustic wave detectors that receive acoustic waves generated from the object, convert the acoustic waves into an electrical signal, and output the electrical signal； and an information acquisition unit that acquires information of the object, based on the electrical signals, wherein the information acquisition unit acquires, for each of the acoustic wave detectors, a change in the intensity of the electrical signal, after the object that has been injected with a contrast agent is irradiated with light that decomposes the contrast agent, and acquires information relating to blood flow, based on the change in the intensity of the electrical signal.
