An X-ray inspecting apparatus, for picking up images from X-rays transmitted through an area of inspection of an object on a plurality of detection surfaces to reconstruct an image of the area of inspection, the X-ray inspecting apparatus comprising: a) a plurality of X-ray detectors, fewer in number than the plurality of detection surfaces, for picking-up images on said plurality of detection surfaces; b) a detector driving unit for moving independently a first portion and a second portion of said plurality of X-ray detectors; c) an X-ray output unit for outputting X-rays such that the X-rays transmitted through said area of inspection enter said plurality of X-ray detectors having been moved to a plurality of image pick-up positions to provide said detection surfaces; and d) a control unit for controlling operation of said X-ray inspecting apparatus; wherein said control unit includes: e) an image acquisition control unit for controlling said detector driving unit and a timing of exposure by each X-ray detector, f) an X-ray output control unit for controlling said X-ray output unit, and g) an image reconstruction processing unit for reconstructing image data of said area of inspection, based on data of intensity distribution of the X-rays transmitted through said area of inspection, picked-up on said plurality of detection surfaces; and characterized in that: h) said image acquisition control unit and said X-ray output control unit are adapted to execute, in parallel: h1) a process of image pick-up by said first portion of said plurality of X-ray detectors at a first position among said plurality of image pick-up positions; and h2) a process of moving said second portion of said plurality of X-ray detectors to a second position different from said first position among said plurality of image pick-up positions. a) a plurality of X-ray detectors, fewer in number than the plurality of detection surfaces, for picking-up images on said plurality of detection surfaces; b) a detector driving unit for moving independently a first portion and a second portion of said plurality of X-ray detectors; c) an X-ray output unit for outputting X-rays such that the X-rays transmitted through said area of inspection enter said plurality of X-ray detectors having been moved to a plurality of image pick-up positions to provide said detection surfaces; and d) a control unit for controlling operation of said X-ray inspecting apparatus; e) an image acquisition control unit for controlling said detector driving unit and a timing of exposure by each X-ray detector, f) an X-ray output control unit for controlling said X-ray output unit, and g) an image reconstruction processing unit for reconstructing image data of said area of inspection, based on data of intensity distribution of the X-rays transmitted through said area of inspection, picked-up on said plurality of detection surfaces; and characterized in that: h) said image acquisition control unit and said X-ray output control unit are adapted to execute, in parallel: h1) a process of image pick-up by said first portion of said plurality of X-ray detectors at a first position among said plurality of image pick-up positions; and h2) a process of moving said second portion of said plurality of X-ray detectors to a second position different from said first position among said plurality of image pick-up positions. h1) a process of image pick-up by said first portion of said plurality of X-ray detectors at a first position among said plurality of image pick-up positions; and h2) a process of moving said second portion of said plurality of X-ray detectors to a second position different from said first position among said plurality of image pick-up positions.