In an X-ray tomographic imaging system and method, an object to be inspected is irradiated with X-rays from an X-ray source to obtain an X-ray transmission image of the object. The X-ray transmission image is converted by an X-ray fluorescence image intensifier into a detection image. The intensity of the detection image is also intensified by the X-ray fluorescence image intensifier. A photo-electric converter converts the intensified detection image from the X-ray fluorescence image intensifier into an electrical signal. The object to be inspected is held by an object holder rotatably at a position in proximity to the X-ray source and movably in a direction of the axis of rotation of the object and a direction perpendicular to the rotation axis. The electrical signal from the photo-electric converter is processed to a cross-sectional image.