PURPOSE: We evaluated the results of the displaced supracondylar fractures in children treated by closed reduction and cast immobilization, closed reduction and crossed K-wires fixation or open reduction with minimal incision and crossed K-wires fixation. MATERIALS AND METHOD: We retrospectively reviewed the results after 1 year of the treatment of 71 extension-type fractures (Gartland type II - 19 cases, type III - 52 cases) of supracondylar humeral fractures in children under age of 8 years. Closed reduction was impossible in 20 cases (1 type II, 19 type III) and we performed open reduction with minimal incision and cross percutaneous pinning. We measured Baumanns angle and range of motion of elbow and evaluated the results by Flynns criteria. RESULT: By Flynns criteria, 91.5 % of satisfactory (excellent, good) results in cosmetic factor and 97.2 % in functional factor. The result of closed reduction and percutaneous pinning is more excellent in functional factor and that of the minimal open reduction and percutaneous pinning in cosmetic factor but over all satisfactory results were similar. CONCLUSION: The treatment of the displaced supracondylar humeral fractures in children needs accurate and delicate reduction and firm fixation to prevent deformity and to preserve function of the elbow. Open reduction with minimal incision instead of general incision for the manually irreducible supracondylar humeral fractures would be a reliable and convenient method for the treatment of supracondylar humeral fractures in children.