The authors reviewed 22 cases of adolescent femoral shaft fractures treated during the period from January, 1958 to June 1992. Seven cases were treated conseratively, eleven by open reduction and intenal fixation with DCP, and four by closed intramedullary nailing. The patients treated with traction and casting showed more often complications such as angular deformity and bone shortening than in the operative methods. In comparing with those cases of plating, the patients of intramedullary nailing had statistically significant shorter ansthesic time and less blood loss in operation. All of the fractures treated with the intramedullary nails healed without malunion or leg length discrepancy, and there was no evidence of growth plate arrest. Results of this study suggest that closed intramedullary nailing of femur fractures in aldolescents is an effective treatment option.