From January of 1987 to July of 1994, 83 patients with acute aortic dissection were treated at our institution. Of these, 7 patients (8%) sustained acute leg ischemia. Angiography showed that one patient had arterial occlusion at the abdominal aorta, three had occlusion at the right common iliac artery, and one had severe right common iliac artery stenosis. Four patients with acute type A dissection underwent emergency replacement of the aortic arch and/or ascending aorta. Three of them were discharged, but one patient died due to renal failure and multiple organ failure. In three patients with acute type B dissection, one with aortic rupture was successfully treated by replacement of the descending thoracic aorta; of the other two who received bypass operations for leg ischemia, one died due to myonephropathic metabolic syndrome and sepsis which were caused by a delay in surgery. In conclusion, emergency thoracic aortic repair should be performed in acute type A dissection with leg ischemia, whereas bypass operation for ischemic leg should be considered in patients of acute type B dissection with leg ischemia when they are not complicated with rupture or visceral ischemia.