The ankle fracture with diastasls of distal tibiofibular joint is caused by an axial loading force with concomitant external rotation and associated with severe ankle fracture in addition to talai subluxation due to rupture of the distal tibiofibular syndesmosis. In order to restore the normal ankle mortise, operative anatomical reduction and temporary stabilization of the syndesmosis is mostily required until early ligament healing is present. Twelve cases among ninety-six cases of the ankle fracture were associated with diastasis and treated in the Department of Orthopedic Surgery, Kyungpook National University Hospital during the period from January, 1988 to May, 1991. We analysed these cases according to injury mechanism, radiographic criterion, the patterns of associated medial and lateral injury and treatment result. The results obtained were as follows; 1. The incidence of trauma was most frequent in 5th decade(5 cases). 2. Diastasls was produced by 3 mechanism according to Lauge-Hansen classification : (pronalion-external rotation : 7, Suplnatlon-external rotation : 3, pronation-Abduction;2). 3. All were associated with fibular fracture : proximal fibular fracture was most common (7cases). 4. All had disruption of the medial structures (medial ligament rupture 3, medial malleolusfracture 9). 5. Although the cases were small, there seems no significant differences between transfixation group and unfixation group when accurate anatomical restoration of the distal tibiofibular syndesmosis was achieved.