Supracondylar fracture of the humerus is the most common elbow fracture in children. It can be complicated by Volkmanns ischemic contracture, nerve injury, deformity of elbow, joint stiffness, and myositis ossificans, etc. even after the treatment. Various methods of treating displaced supracondylar rracture have been described, and the indications for open reduction and internal fixation are relatively established well. The surgeon, however, might be in trouble with making decision for closed reduction, whether to maintain by casting or by percutaneous pinning. From fan. 1990 to May 1990, 117 patients of supracondylar tracture had been treated in Seoul Adventist Hospital, and 82 patients of them were challenged initially by closed reduction and casting. Among them, 51 cases have been followed more than 1 year, and they are reviewed. 1. The average age was 7.2 years, and the patient population consisted of 33 boys and 18 girls. 2. 3 cases of nerve injuries, 2 cases of ipsilateral forearm bone fractures, 2 cases of impending Volkmanns ischemic contracture and 1 case of cerebral contusion were associated with supracondylar fracture. 3. Fracture pattern were classified as flexion type of 1 case and extension type of 50 cases. According to Gartland classification, type II was 16 cases(31.4%), type III-A was 27(52.9%) and III-B was 7(13.7%). Of all, 28 cases(54.9%) were comminuted and 23 were non-comminuted. On the other hand, 14 cases(27.5%) were oblique fracture and 37(72.5%) were transverse one, classified by pattern of fracture line. 4. Success rate of closed reduction and casting were 56.3% in Garland type II, 33.3% in type III-A, 42.9% in type III-B. In comminuted fracture, it was 21.4% and 65.2% in non-comminuted one. Success rate was 7.1% in oblique fracture, and 54.1% in transverse one. This suggests that comminuted fracture or oblique fracture should not be tried by closed reduction and casting but by percutaneous pinning. 87.5% of non-comminuted and transverse fractures were treated successfully by initial closed reduction and casting, and it also suggests that closed reduction and casting should be done only in this case selectively. 5. By Flynns criteria the results were excellent in 9 cases, good in 8, fair in 3 and poor in 1 with casting. Percutaneous pinning resulted in 15 excellent, 10 good, and 1 fair cases. Open reduction and internal fixation resulted in 2 excellent and 2 good cases.