Objective To evaluate the mid-term outcome of impacting bone graft and strut graft in treating osteonecrosis of the femoral head (ONFH) and to compare the effects of fibular autograft and allograft for strut graft. Methods From August 2004 to December 2004, 40 cases (58 hips) of ONFH were treated with impacting bone graft and nonvascular fibular autograft (autograft group) or allograft (allograft group). In the autograft group, 20 cases (27 hips) included 17 males (23 hips) and 3 females (4 hips) with an average age of 41 years (22-53 years); 22 hips were at stage II and 5 hips at stageIII according to the classification system of Association Research Circulation Osseous (ARCO). In the allograft group, 20 cases (31 hips) included 17 males (25 hips) and 3 cases females (6 hips) with an average age of 40 years (18-55 years); 23 hips were at stage II and 8 hips at stage III according to the classification system of ARCO. The outcome was evaluated both cl inically by Harris hip score (HHS) and radiologically by X-rays. The related compl ications were recorded. The end-point of observation was determined when further salvage operation or total hip arthroplasty was needed. Results All cases were followed up for 36-40 months (mean 37.5 months), 25 hips (92.6%) preserved femoral heads in autograft group and 28 hips (90.3%) in allograft group. Harris score in autograft and allograft groups was increased significantly from 70.82 ± 8.26 and 69.94 ± 9.59 before operation to 86.36 ± 6.27 and 87.45 ± 7.03 at the last follow-up, respectively, indicating a significant difference between before and after operation in two groups (P lt; 0.05), but no significant difference between two groups (Pgt;0.05). The radiological results showed that 17 hips (63.0%) in autograft group and 21 hips (67.8%) in allograft group improved or had no further collapse; and 20 hips (74.1%) in autograft group and 22 hips (71.0%) in allograft group were in good repair, indicating no significant difference between two groups (P gt; 0.05). The postoperative compl ication occurred after weight-bearing walk in the autograft group and during wound heal ing stage in the allograft group. Conclusion For selected cases of femur head necrosis, the treatment with modified impacting bone graft and strut graft has a satisfactory mid-term outcome. The results of fibular autograft and fibular allograft had no significant difference.