In an X-ray inspection, influence of the beam hardening on the attenuation of the X-rays is reduced, image noise is reduced, and image contrast is more improved, and a more quantitative inspection performance to object thicknesses is secured in the X-ray paths. A detection unit (26) with a detector (24) is provided. The detection unit detects transmitted amounts of the X-rays generated by an X-ray generator (23) and transmitted through the object in each of n-number X-ray energy bins (n is a positive integer of 2 or more) which are set in advance to the X-rays, and outputs detection signals corresponding to the transmitted amounts. An information acquisition unit (51) acquires, based on the detection signal, information showing a thickness t of the object and an average linear attenuation coefficient µ in a transmission direction of fluxes of the X-rays, in each of the energy bins. A pixel data calculation unit (52) calculates, based on the acquired information, pixel data composed of pixel values each obtained by multiplying addition information by the thickness t. The addition information is obtained by mutual addition of the average linear attenuation coefficients µ in the respective energy bins.
