Objective To find an effective method of surgical treatment of fibrous dysplasia of bone involving the proximal femur. Methods From January 2001 to January 2006, 57 patients with fibrous dysplasia of bone involving the proximal femur were treated. There were 29 males and 28 females, aging 8-50 years (mean 22 years). Thirty-five patients wereinvolved one bone and 22 patients were involved more than two bones. According to Guille’s classification, there were 34 cases of type A, 8 cases of type B, 8 cases of type C and 7 cases of type D. Fourteen cases compl icated by coax varus and the neck-shaft angle of femur was 78° on average (55-100°). The duration of the disease was 2.3 years on average (4 months to 10 years). The choice of the various operative procedures depended on the qual ity of the bone and the extent of the lesion. When the qual ity of the bone was good, then curettage and bone-grafting was performed. When the qual ity of the bone was poor, curettage and bone-grafting combined with internal fixation was performed. Medial displacement valgus or valgus osteotomies were used to treat fibrous dysplasia of bone involving the proximal part of the femur with coax varus. Results All patients were followed up for 6 months to 5 years with an average of 2.8 years. All bone graft were absorbed sl ightly at 3 months and markedly at 10 to 14 months postoperatively. The femoral mechanical al ignments were corrected completely radiologically in patients compl icated by coax varus; the average neck-shaft angle was corrected from 78° (55-100°) preoperatively to 122° (95-130°) postoperatively. The relative length of femur was increased 1.8-3.6 cm (mean 2.7 cm). After operation, 49 patients could walk without support, 5 with claudication, 3 ambulated with the aid of unilateral cane. Pain disappeared in 52 patients and pain was improved in 5 patients. No infections and recurrent fracture and progression of the deformity occurred in all patients. Conclusion Impactionallograft is the key of prompting allograft incorporating fully and preventing pathological fracture. An effective internal fixation must be used when the qual ity of the bone is poor. Medial displacement valgus or varus osteotomies can correct varus deformity, improve function, as well as restore biomechanical axis of femur. It is also able to effectively eradicate lesions and prevent recurrence.