An object information acquiring apparatus of the present invention has a conversion element receiving an acoustic wave generated in and propagated from an object and converting the acoustic wave to an electric signal, a holding unit holding an acoustic matching member that acoustically matches the object to the probe, a temperature measuring unit measuring temperatures at a plurality of positions in the acoustic matching member, a reconstruction processing unit acquiring a sound speed of the acoustic matching member and characteristic information of the object based on the sound speed and the electric signal, and a controlling unit performing control based on the temperatures measured at the plurality of positions.
