A radiation imaging apparatus performs radiation image obtaining processing in accordance with an exposure instruction, and obtains a radiation image. Then the radiation imaging apparatus performs offset correction for the obtained radiation image, and displays it. The radiation imaging apparatus determines, in accordance with a predetermined criterion, whether or not offset images obtained by offset image obtaining processing are stable over time. Then, if it is determined that the offset images are not stable, offset correction is performed by using an offset image obtained by performing offset image obtaining processing, following the obtaining of the radiation image. If it is determined that the offset images are stable, the offset correction is performed by using an offset image obtained before the obtaining of the radiation image.