Purpose:To analyze results of treating acromioclavicular injuries using clavicle hook plates. Materials and Methods: Between February 2008 and April 2010, 18 patients with acromioclavicular joint injury treated by clavicle hook plates were reviewed. Using the Rockwood classification, 7 dislocations were classified as type III injuries and 11 as type V injuries. Implant removal was done at least 3 months from initial fixation. Simple X-rays were taken for comparing the state of reduction, and clinical outcomes were evaluated by the Korean Shoulder Scoring System and the American Shoulder Elbow Society score. The average follow-up period was 9 months. Results: On weight bearing X-rays, the average coracoclavicular distance showed a 114% increase compared to the contralateral side at the time of injury. It decreased to 23% by the last follow-up. The mean Korean Shoulder Scoring System and the American Shoulder Elbow Society score were 80 and 74 at the last follow-up. Conclusion: The immediate stability these plates provide allows rapid rehabilitation. Clavicle hook plate fixation for acromioclavicular joint dislocation is considered an effective method for ensuring satisfactory results both radiologically and clinically.