An image processing apparatus that processes a radiation image obtained from a detector in which a plurality of pixels are two-dimensionally arranged includes: an obtainment unit that obtains a radiation image; a control unit that controls, in accordance with radiation dose characteristics of a first pixel in the detector and a first pixel value of the first pixel in the radiation image, a weighting coefficient for the first pixel value of the first pixel and a weighting coefficient for second pixel values that are different from the first pixel value; and a correction unit that corrects the first pixel value in the obtained radiation image based on the weighting coefficients.