Recently, the incidence of pelvic bone fractures has been increased with increment of the volume of traffic. We reviewed 318 cases of pelvic bone fractures treated at the department of orthopaedic surgery of Hanyang University Hospital during the period from May, 1972 to December, 1980. The age and sex distribution, cause and classification of fractures, type of treatment, associated injuries and complications were recorded and investigated. The results obtained were as follows: 1. There were one hundred and ninety four (61%) male and one hundred and twenty four (39%) female, and one hundred and ninety seven patients (62%) in this entire series were aged from twenties to forties. The most common victims were in active persons. 2. The most common causative injury was traffic accident. 3. Two hundreds and thirteen (67%) cases were stable fracture and one hundred and five (33%) cases were unstable fracture, which were classified by Kanes classification. 4. The fracture of the femur was most commonly associated bone and joint injuries and the injury of the lower urinary tract was also most commonly associated soft tissue injuries. 5. All of the cases, except 3 cases of the avulsion fracture, were treated with conservative treatment. The remaining 3 cases were treated with surgical treatment, 6. The mortality rate was 5.3%, and the most common cause of death was hemorrhagic shock in 70.6% of the entire fatal cases in this series.