Provided is an object information acquiring apparatus having: a light source； an optical transmission system that transmits light from the light source； a photoacoustic probe including an irradiating end that irradiates the light onto an object and a receiver that receives an acoustic wave generated from the object, onto which the light is irradiated； a processor that acquires information on the object interior on the basis of the acoustic wave； a display device that displays information on the object interior； a holder that stores the photoacoustic probe and covers the irradiating end； and a light quantity meter that measures quantity of irradiated light, wherein the irradiating end can irradiate light in a state being cover by the holder.
