The present invention comprises: a first X-ray irradiation apparatus and a second X-ray irradiation apparatus for irradiating a subject with X-rays； an X-ray generation unit supporting so that first and second X-rays irradiated onto the subject are detected by a set detector when the subject is irradiated with the first and second X-rays from the first and second X-ray irradiation apparatuses, respectively； and a mode selection unit for allowing selection of any one mode from among a 2D imaging mode and 3D imaging mode, wherein the angles with respect to the subject of the first and second X-ray irradiation apparatuses are determined on the basis of said any one mode selected by means of the mode selection unit from among the 2D imaging mode and 3D imaging mode. According to the present invention, the mode can be easily selected according to need from among the 2D imaging mode and 3D imaging mode.
