【Abstract】 Objective To evaluate the effectiveness of percutaneous fixation with il iosacral screw in the management of unstable pelvic fractures. Methods From March 2003 to January 2007, 15 patients with unstable pelvic fractures were treated by percutaneous fixation with il iosacral screws. There were 6 males and 9 females, aged 21-56 years. Fractures were caused by traffic accident in 8 cases, high fall ing in 6 cases and crushing injury in 1 case. The disease course ranged from 4 hours to 3 days. Of 15 patients, 7 had fractures of pubium and sacrum; 2 had fractures of il ium and sacrum; 4 had dislocation of sacroil iac joint with fractures of pubic rami; and 2 had dislocation sacroil iac joint with fracture of sacrum of pubium. Anterior fixation was performed by means of plating in 3 cases, by external fixation in 7 cases, and by both in 5 cases. Results The blood loss was from 1 000 to 1 500 mL in 4 patients with acetabular fracture and about 50 mL in the others. The average operative time was 153.6 minutes (range, 60-305 minutes). Fifteen patients were followed up 6 months to 3 years with an average of 18months. According to Matta criterion for fracture reduction, the results were excellent in 14 cases and good in 1 case. After a follow-up of 28.8 months, fracture union was achieved in all patients. Screw loosening occurred in 1 case, pain of lumbosacral region in 3 cases after tiredness and mild claudication in 2 cases. Nine patients returned to their occupation, three patients changed occupation, and 3 patients could not work at last follow-up. According to Majeed functional scoring, the results were excellent in 11 cases and good in 4 cases. Conclusion Percutaneous il iosacral screw fixation is a useful method in treatment of unstable pelvic fracture.