PURPOSE: To provide an X-ray bed apparatus provided with a mechanical interlocking mechanism for standing up and laying down and moving up and down by a simple structure with only one motor.

CONSTITUTION: This X-ray bed apparatus wherein a top board part on which a subject to be examined being an object of X-ray photographing is placed can be moved up and down and stood up and laid down, is provided with a screw shaft 3 and a nut 7 for converting regular and reverse rotation of a motor l to moving up and down of an X-ray bed, racks 8 and 9 which are each stood vertically and have gear teeth engraved on side faces facing each other and pinions 10 and 11 being fittable to the racks 8 and 9. In addition, a reduction gear 16 in which one end of an input shaft is connected with the rotating shaft of the pinion 10 through a clutch 12 and another end of the input shaft is connected with the rotating shaft of the pinion 11 through a clutch 13, and the top board part 19 which can be stood up and laid down by rotation of the output shaft of the reduction gear 16.