PURPOSE: To evaluate unilateral external fixation when applied as the standard treatment of displaced femoral shaft fractures in children. MATERIALS AND METHODS: From 2000 through 2004, we used a unilateral external fixator (Any-fix(R)) to treat 24 femoral shaft fractures. The average age of the patients was 8.3 years (range, 5.6 to 14.8). 16 fractures were isolated, and 8 were associated with polytrauma. There were 4 open fractures. Patients were followed clinically and radiologically until healing and at 1 year. RESULTS: Average time of external fixation was 97 days (range, 57 to 130 days). All patients regained the normal range of motion of knee joint without significant residual leg length discrepancy or growth disturbance. There were no nonunion, or rotationary deformities. There were 26 pin tract infection (total pin number: 108) (24%), all of which were resolved with antibiotics. No patient developed osteomyelitis. There were two refractures after fixator removal. There was one case of reduction loss and one of valgus deformity. CONCLUSION: The external fixation is a useful alternative for operative management of femoral shaft fractures because of minimal invasive operation, and early mobilization in prepuberty.