An object information acquiring apparatus is used that includes: an ultrasound probe that receives an acoustic wave propagating from an object and outputs an electric signal; and a processor that generates an image of the inside of the object, using the electric signal. The processor creates a frequency distribution of pixel values included in a region of interest including a point of interest in the image, classifies the point of interest on the basis of the shape of the frequency distribution and the position of the point of interest in the frequency distribution, and determines a pixel value of the point of interest on the basis of a classification result of the point of interest.