Posterior shoulder dislocation is the most common missed major joint dislocation. The glenohumeral joint is ball and socket joint. It is less stable so it is commonly sujected to instability. Classification of posterior shoulder dislocation according to the aetiology, direction. Mechanism of injury, and violation., Good examination and X-ray, and CT radiography is important in the diagnosis. Treatment consist of physiotherapy. Open surgery, and endoscopic.