A photoacoustic apparatus according to the present invention includes an electrical stimulation unit configured to apply a voltage to a subject while light irradiation is being performed a plurality of times, and a processing unit configured to acquire, among a plurality of signals, subject information using at least part of signals corresponding to photoacoustic waves generated in a period from an extraction start timing determined in accordance with an application start timing of the voltage to when a first time period starting from the application start timing and ending at an application end timing of the voltage passes, while not using a signal corresponding to a photoacoustic wave generated outside the period from the extraction start timing to when the first time period passes.
