A photoacoustic apparatus according to the present invention includes an electrical stimulation unit configured to apply a voltage to a subject, and a processing unit configured to set a light irradiation timing such that the subject is irradiated with pulsed light at least once in a period from an irradiation 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, and to set the light irradiation timing such that the subject is not irradiated with pulsed light outside the period from the irradiation start timing to when the first time period passes.
