In the radiographic apparatus of this invention, a composite image generating device generates a composite high-voltage/low-voltage image for every time of the same high voltage/low voltage based on a plurality of high-voltage/low-voltage images successively acquired by a high-voltage/low-voltage image acquiring device. Based on the composite high-voltage/low-voltage image generated by the composite image generating device, a subtraction processing device carries out a subtraction process concerning high-voltage images and low-voltage images, to acquire subtraction images. Thus, a mistake by arithmetic processing is made inconspicuous without causing a dose shortage.