An apparatus for X-ray photography includes a first X-ray source, a first driving device, and an image detecting device. The first X-ray source has a light emitting end, provided with a block element. The first X-ray source generates an X-ray beam, and the block element is used for constraining a projection field of the X-ray beam, so that the X-ray beam has a first boundary. The X-ray beam is cast onto an object, and the object has a reference center and an imageable area. The first driving device is used for driving the first X-ray source to rotate around the object within an angle range with the reference center of the object as a center, so that when the first X-ray source is located at a first position, the first boundary passes through the reference center.