Aiming　at　the　difficulty　in　X　ray　diagnosis　for　the　sacroiliac　joint＇s　subluxation,　the　sacroiliac　joint　images　for　a　patient＇s　physiological　state　and　pathological　state　are　analyzed　in　this　paper.　We　find　that　the　image　of　the　iliac　pro-up　shift　7mm　is　similar　to　that　of　the　pelvic　rotation　10　degrees　around　the　Y　axis,　and　the　image　of　the　iliac　external　rotation　5　degrees　is　similar　to　that　of　the　pelvis　rotation　5　degrees　around　the　Z　axis.　These　results　may　easily　lead　to　a　massage　doctor＇s　misdiagnosis　or　leak-diagnosis.