PROBLEM TO BE SOLVED: To have a plurality of X-ray sources in an identical X-ray source retention device.SOLUTION: An X-ray source retention device includes: a plurality of X-ray sources 13 irradiating a subject with X rays a collimator 15 collimating the X rays at a single opening part and X-ray source position control means enabling the plurality of the X ray sources to move to a position substantially identical to the opening part so that an X-ray focal position remains substantially unchanged even when any of the X-ray sources is used.
