The ankle joint is a modified complex hinge joint which plays an important role in weight bearing, walking and standing. Hence, the ankle injuries include not only fractures of bone but often also the rupture of ligaments and soft tissues, so if the structures were not accurately repaired, many complications may be developed. The authors have reviewed a series of 70 cases of ankle fractures which were treated in department of orthopaedic surgery of Inha hospital from January 1988 to February 1992. Among the seventy cases, 41 patients (59.4%) were male, and 28 patients (40.6%) were female. Average age was 41.4 years and 3 cases (4.35%) were open fracture. The most common cause was slipping 34 cases (48.6%) and the other causes were traffic accident 23 cases (32.9%), fall from height 6 cases (8.6%), direct blow 5 cases (7.0%) and sports injury 2 cases (2.9%) in order. The rusults obtained form this study were as follows. l. According to the classification fo Lauge-Hansen, the most common fracture mechanism was supination-external rotation injury (24 cases: 34.4%). 2. Among them, 51 cases were treated by operative treatment and 19 cases by conservative treatment. 3. Ten cases (14.3%) in this series were complicated; traumatic arthritis in 7 cases, infection in 2 cases and nonunion 1 case. 4. Open reduction and internal fixation and early anatomical reduction were better than closed reduction and delayed reduction. 5. The incidence of traumatic arthritis occured higher in the cases treated with closed method.