Posterior dislocation of shoulder is rare and its possibility is only 2.1% of shoulder dislocations. The mechanism of injury may be caused by direct or indirect forces. We reported a case of 22-year-old male who suffered from right shoulder pain due to traffic accident. Persistant right shoulder pain and limited range of motion was noted. Under an impression of right neglected shoulder posterior dislocation, we use the modified McLaughlin procedure and get good clinical result.