Diastasis of the ankle joints was associated with not only ankle fracture but also with ligamentous rupture. Since keeping anatomical reduction and giving secure stability to the injured ankle is the gole of the treatment for a good outcome, diastasis should not be overlooked from the first time. To obtain this goal, thorough understanding of diastasis and clear-cut diagnostic guide is important. Seventy one patients of ankle diastasis treated at Presbyterian Medical Center from Jan. 1979 to Dec. 1985 were analyzed in clinical and radiological aspect. The results obtained from this study were as followings. l. Among the 71 diastasis patients, male was predominantly 90%. The average age was 32 years old of age. 2. The main cause of diastasis was traffic accident (42 cases) and the other causes were falling from a height, sport injury in order of frequency. 3. In classification of the Lauge-Hansen, the most common mechanism that causes ankle diastasis was supination-external rotation (47.8%). 4. On the degree of the diastasis, complete type was 32.4%, and incomplete type was 67.6%. 5. 67.8% of the ankle injury patients developed ankle diastasis. 6. The average transfixation time was 11 weeks. 7. By the Meyers assessment, clinically 81.6%, radiologically 87. 3% good result can be obtained. 8. Good result could be achieved by early accurate diagnosis and proper operative intervention.