The ankle, which at times bears up to five times the body weight, is the most congruous joint of the lower extremity. Recently, importance of early joint motion and weight bearing after anatomical reduction & rigid internal fixation of the displaced ankle fracture was emphasized. Therefore, we studied prospectively, fifty-two patients with displaced ankle fractures admitted to the Department of Orthopedic Surgery, Severance hospital during a period of 4 years from January 1985 to December 1988. In fifty-two patients, group I (24 cases)were treated with early joint motion and weight bearing without cast immobilization and group II (28 cases) were treated with cast immobilization for long duration after open reduction and rigid internal fixation. The result of an average 15 months follow up of these patients were as follows. l. In displaced ankle fracture, early recovry of joint motion was obtained in early joint motion and weight bearing group after accurate anatomical reduction and rigid internal fixation. 2. In clincal evaluation, 95.8% resulted to satisfactory in group I, whereas 85.8% in group II. 3. In radiologic evaluation, 95.8% resulted to satisfactory in group I, whereas 82.1% in group II. 4. In lateral malleolar fracture, accurate reduction and fixation with plate and screws was important. 5. Syndesmotic ligament should be repaired and weight bearing was allowed without removal of transfixing screw. 6. Reduction of lateral malleolus made reduction and fixation of medial malleolus easy, and thus maintaining talar tilt angle. 7. Anatomical repair of deltoid ligament was needed for stability of ankle joint and prevention of local degenerative change.