PURPOSE: To enable the fixing of an object to be examined efficiently and accurately by providing an auxiliary belt at a part of a fixing belt for fixing the body part of an object to be examined on a top board to fix an arm part of the object to be examined.

CONSTITUTION: After a person P to be examined is placed on a top board 11, an operator inserts a fixing member 11 having a fixing belt 15 inserted into an insertion port 14a into an isolating part 13 between a rail 12 and the top board 11 on the side of a body part P1 at a point desired to fix the person P to be examined. Then, the operator joins fasteners 15a and 15b one upon another applying a tension to the fixing belt 15 to fix the body part P1. Then, when only one fixing belt 15 is used and the person P to be examined may move during photographing, two fixing belts 16 for fixing askew are inserted into insertion ports 14a and 14c of the fixing device 14, crossing each other and just as the fixing belt 15, the fasteners 16a and 16b are joined one upon another to further fix the body part P1. Then, the operator joins fasteners 17a and 17b of an auxiliary belt 17 one upon another to fix both arms P2.