Six surgical cases of localized abdominal aortic dissections experienced from 1977 to August, 1992 comprised 1.1% of all true aneurysms of the abdominal aorta (563 cases) and 2.5% of all aortic dissections (242 cases) for the same period. The mean age of the 6 patients at operation was 70 years (range from 62 to 74 years, 2 males, 4 females). All dissections were localized at the infrarenal abdominal aorta and one case showed three-channeled dissection. All cases were diagnosed preoperatively and prosthetic graft replacement was performed. Localized abdominal aortic dissection was reported in only 30 cases, including our cases, in the Japanese literature. Compared to thoracic aortic dissection, the development of symptoms is slow, age is high and the condition is often accompanied by hypertension and atherosclerosis.