Eighty-five patients with thoracic aortic aneurysm (TAA) (36 dissection, 49 non-dissection) underwent surgical intervention in our service from December 1985 to March 1997. 31 patients aged over 70 (aTAA) were compared with 54 patients under 69 years of age (non-aTAA) about preoperative condition, surgical invasion, and operative morbidity and mortality. No significant differences were observed in preoperative associated condition and laboratory data between two groups except more non-dissection were included in aTAA (74.2%) than non-aTAA (48.1%). There were no significant differences in intraoperative variables and endotracheal intubation time and ICU staying time were shorter in aTAA (not significant). No significant differences were revealed in operative morbidity, mortality and five-year actual survival rate between two groups. 16.1% of early mortality and 9.7% of hospital mortality for operated aTAA were acceptable, which let us conclude that aTAA must be operated positively before rupture by careful selection considering life expectancy, evaluation of risk factors or reserved physiological status, and surgical invasion.