An object information acquiring apparatus that acquires information inside an object by receiving an acoustic wave that has arrived from inside the object through a layer having an acoustic impedance that is different from that of the object, and analyzing the acoustic wave, the object information acquiring apparatus comprises an acoustic wave probe that receives an acoustic wave and converts the acoustic wave into an electric signal； a whole image generation unit that generates a whole image, which is an image indicating information inside the object, based on the electric signal after the conversion； a partial image generation unit that extracts a partial image, which is a part of the whole image, from the whole image； and a similar image search unit that searches an area similar to the partial image, from the whole image.
