The present invention relates to an adjusting positioner for a radiation device, comprising: a clamping device detachably connected to the radiation device to clamp said radiation device; a supporter to which said clamping device is connected and a slide path is defined therebetween, wherein the clamping device clamping said radiation device is movable along said slide path in a predetermined direction; and an adjusting device coupled with said clamping device so as to drive said clamping device to move along said slide path. Since the present invention employs above technical solution, it is easy to adjust the position of the radiation device for example, X-ray device, so that the precisely positioning for the radiation device is achieved and a satisfying positioning accuracy is able to obtain.