The utility model relates to a positioning holder of an X-ray machine, which is suitable for an X-ray machine and an X-ray film, and comprises a base, a supporting frame and an adjustable positioning frame. The support frame is fixed on the base and has a support surface for supporting the X-ray film. The adjustable positioning frame can be rotationally arranged on the base relative to the support frame. The adjustable positioning frame has a butting surface for the X-ray machine to buttress.一種X光機之定位持片器，適用於一X光機及一X光片，包含一基座、一承靠架及一調整式定位架。承靠架固定於基座，並具有一承靠面，並用以供X光片承靠。調整式定位架可相對承靠架旋轉地設置於基座，調整式定位架具有一抵靠面，抵靠面用以供X光機抵靠。
