Twelve patients underwent surgical interventions for aortic aneurysms consecutively from September 1986 to September 1990 in the Department of Thoracic and Cardiovascular Surgery, Yeungnam University Hospital. They were all men ranging in age from 25 to 68 years with the mean age of 48 years. Five patients of them had aneurysms involving ascending aorta, one aneurysm involving both ascending and descending aorta, four aneurysms involving descending thoracic aorta, and the others had aneurysms involving abdominal aorta. According to morphological classification, six cases of them were in dissection and the others in fusiform aneurysms. All the cases were pathologically true aneurysms and four of them were in acute status. According to causal classification, seven patients of them had atherosclerosis, three cystic medial necrosis, and the others had syphilis and trauma respectively. Six patients with ascending aortic aneurysm had annuloaortic ectasia with aortic regurgitation and underwent ascending aortic graft and aortic valve replacement[Bentall`s operation]. The others with descending thoracic and abdominal aortic aneurysms underwent Dacron graft replacement. Both hemorrhage necessitating reopening of the chest and wound dehiscence were observed in three patients and hoarseness in one patient. Cerebrovascular accident occurred three and a quarter years postoperatively in one patient and he died two days later. The others were followed up via OPD and have been doing well postoperatively.