5 cases of dissecting aortic aneurysm were reported with a brief literature review. The results were as follows. 1. All five cases were male with hypertension. 2. All of them were DeBakey's Type I. 3. Three of them died within one week after admission. 4. Causes of death were heart failure, hemopericardium, renal failure, one case each respectively. 5. Occurence of aortic insufficiency as complication in one case. 6. Surgery was performed in one case.