An X-ray imaging apparatus comprising: an X-ray generation unit that is adapted to generate an X-ray and irradiates a subject with the X-ray; a subject positioning rotation table unit that is adapted to adjust an angle of the subject with respect to an optical path direction of the X-ray and an incident position of the X-ray to the subject ; an X-ray image detection unit that is adapted to detect an X-ray transmitted through the subject ; a detector positioning table unit that is adapted to two-dimensionally move and position the X-ray image detection unit on a surface perpendicular to an X-ray; a processing unit that is adapted to calculate a sectional image of the subject from a plurality of X-ray images obtained by moving the X-ray image detection unit by the detector positioning table unit ; and a control unit that is adapted to control each of the units , wherein the X-ray image detection unit is adapted to obtain X-ray images at different angles of the subject with respect to the optical path direction of the X-ray, wherein the angle is incrementally changed by the subject positioning rotation table unit , the detector positioning table unit is configured to move the X-ray image detection unit after the incrementally changed angle has reached half rotation, and the moved X-ray image detection unit is adapted to again obtain the X-ray images at different incrementally changed angles of the subject with respect to the optical path direction of the X-ray, characterised in that the moving distance (d) of the detector positioning table unit is 1/n, n being a natural number excluding 1, of a size of a pixel that constitutes the X-ray image detector . an X-ray generation unit that is adapted to generate an X-ray and irradiates a subject with the X-ray; a subject positioning rotation table unit that is adapted to adjust an angle of the subject with respect to an optical path direction of the X-ray and an incident position of the X-ray to the subject ; an X-ray image detection unit that is adapted to detect an X-ray transmitted through the subject ; a detector positioning table unit that is adapted to two-dimensionally move and position the X-ray image detection unit on a surface perpendicular to an X-ray; a processing unit that is adapted to calculate a sectional image of the subject from a plurality of X-ray images obtained by moving the X-ray image detection unit by the detector positioning table unit ; and a control unit that is adapted to control each of the units , wherein the X-ray image detection unit is adapted to obtain X-ray images at different angles of the subject with respect to the optical path direction of the X-ray, wherein the angle is incrementally changed by the subject positioning rotation table unit , the detector positioning table unit is configured to move the X-ray image detection unit after the incrementally changed angle has reached half rotation, and the moved X-ray image detection unit is adapted to again obtain the X-ray images at different incrementally changed angles of the subject with respect to the optical path direction of the X-ray, characterised in that the moving distance (d) of the detector positioning table unit is 1/n, n being a natural number excluding 1, of a size of a pixel that constitutes the X-ray image detector . <EOS>