Objective To investigate the surgical treatment effectiveness of acetabular transverse and posterior wall fractures by Kocher-Langenbeck approach. Methods Between January 2002 and February 2009, 17 patients with acetabulartransverse and posterior wall fractures were treated with Kocher-Langenbeck approach and fracture reduction and fixation. There were 12 males and 5 females with an average age of 33.4 years (range, 20-65 years). The disease causes were traffic accident in 16 cases and fall ing from height in 1 case. The disease duration was 6 hours to 11 days. According to Letournel classification, all fractures were rated as acetabular transverse and posterior wall fractures. Concomitant injuries included posterior hi p dislocation in 3 cases, fracture of extremities in 8 cases, injury of sciatic nerve in 3 cases, craniocerebral injury in 1 case, and l ienal rupture in 1 case. Results The incisions healed primarily and no compl ication of infection and deep venous thrombosis occurred after operation. All patients were followed up 12 to 36 months with an average of 19 months. The X-ray films showed that fracture healed 3 to 5 months after operation. After operation, anatomic reduction was found in 9 cases, satisfactory reduction in 5 cases, and unsatisfactory reduction in 3 cases according to Matta et al criterion. According to modified grading system of Merle D’Aubigne and Postel, the results were excellent in 4 cases, good in 9, fair in 3, and poor in 1 at last follow-up with an excellent and good rate of 76.5%. The nerve function was recovered in patients with sciatic nerve injury at 12 months after symptomatic treatment. Traumatic arthritis occurred in 5 cases, avascular necrosis of the femoral head in 1, and heterotopic ossification in 5 between 9 weeks and 12 months after operation. Conclusion For acetabular transverse and posterior wall fractures, it is important to make adequate preoperative preparation, to get the imaging data, and to perform open reduction andinternal fixation with Kocher-Langenbeck approach as early as possible.