The authors reviewed 3133 consecutive autopsies performed in the 5 year period from 1986 to 1990 in Queen Mary Hospital (Hong Kong), and 96 cases of aortic aneurysms were found. The incidence was 1 in 33 autopsies. The ratio of male to female was 1.8 to 1, and the disease was most common in the eighth decade of life. The majority of death was due to rupture (70%) or related atherosclerotic diseases (14%), and the majority of aneurysms were not suspected before autopsies (62%). Most of the non-dissecting aneurysms were found in the abdominal aorta, the infra-renal portion. For dissecting aneurysms, Daily's type A was much more common. Hypertension was recognized in a high proportion of cases. Accompanying diseases like syphilis, Takayasu's disease, ischemic heart disease, cerebrovascular accident, diabetes mellitus, peripheral vascular disease, and chronic obstructive airway disease were also noted.