Frozen shoulders improve mostly by the conservative management, such as medication therapy and positive physical therapy. Despite the vast majority regain motion and have reduced pain with gentle but persistent exercises, patients do not always spontaneously recover motion. Arthroscopic manipulation may be recommanded in patients whose symptoms last more than 6 months or when the conservative treatment fails and severe stiffness is primarily originated. Nineteen cases of frozen shoulder underwent arthroscopic manipulation under the general anesthesia from February, 1990 to February, 1992. All but one case had shoulder pain and 13 cases(68.4%) had trivial trauma history at the time of symptom onset. One of the chief complaint was the limitation of motion; abduction: 19 cases, external rotation: 17 cases, flexion: 13 cases, extension: 11 cases, internal rotation: 8 cases and adduction: 7 cases. Average abduction range at the time of admission was 63.9°. In the average 23 months follow up(15 months to 3 year 2 months), painless was shown in 13 cases and significantly decreased pain in 6 cases, and all the patients were satisfactory with the results. The range of the abduction motion was changed from 64° to nearly normal. All of the patients improved by 1 month to 4 months, average 2.9 months. We propose arthroscopic manipulation could be recommended in the treatment of frozen shoulder if an appropriate conservative treatment is not effective.