Eighteen children between the ages of 6 and 12 years with unilateral non-united femoral neck fractures were treated by valgus intertrochanteric osteotomy with bone grafting between January 1995 and December 2000. Twelve fractures were judged as Pauwel 3, and 6 as Pauwel 2, and 5 children had avascular necrosis in addition to non-union. The initial treatment included internal fixation in 14 fractures, conservative treatment in 2 fractures, and no treatment in 2. The average interval from injury to osteotomy was 10 months (8-14 months). In each case we used a 90° child or adolescent hip plate modified by making an angle of 120 0 between the blade and shaft portions to simulate an adult Osteotomy plate. All fractures healed after osteotomy and bone grafting; the average time to radiological union was 12 weeks (8-24 weeks). At an average follow-up of 3.5 years (2-6 years), 15 cases were rated good, 2 fair, and 1 poor based on Ratliff’s criteria. Valgus osteotomy with bone grafting provided successful results in treatment of non-united femoral neck fractures in children, even in the presence of avascular necrosis.