Objective To evaluate the primary cl inical effect of proximal femoral nail anti-rotation (PFNAR) in treating femoral intertrochanteric fractures, to summarize operation skills and to analyze correlated curative effective influentialfactors. Methods From July 2006 to May 2007, 19 cases of intertrochanteric fractures (including 8 males, 11 females, aged45-87 years old) were treated with closed reduction and PFNAR fixation. Fractures were caused by fall ing. The locations were left sides in 10 cases and right sides in 9 cases. According to AO classification, there were 14 cases of type A2 and 5 cases of type A3. Operative time, volume of blood loss and weight bear time were analyzed, the condition of fracture union was observed and the hip function was evaluated using Harris criterion after 9 months of follow-up. Results Operative time ranged 23-78 minutes with an average time of 47 minutes, the volume of blood loss ranged 50-120 mL with an average volume of 85 mL, getting-outof- bed time ranged 2-14 days with an average time of 7.4 days; the weight bearing time ranged 10-14 weeks with an average time of 12.4 weeks. No intra-operative femoral fractures and no regional or deep infection occurred during hospital ization period. Seventeen cases were followed up from 3 months to 12 months with an average time of 9.4 months, and achieved bone heal ing within 15-18 weeks with an average time of 16.5 weeks. No compl ications such as delay heal ing, coxa vara or coxa valga, cut-out and screw extraction occurred. Fifteen cases were followed up over 9 months; according to the Harris criterion for evaluation, the results were excellent in 13 cases, good in 1 case and fair in 1 case, the excellent and good rate was 93.3%. Conclusion PFNAR has the advantages of micro invasion, easy-to-perform, less blood loss, less bone loss and stable fixation in treatment of unstable comminuted intertrochanteric fracture, especially in old patients with osteoporosis.