With the aging of the population of Japan and Westernization of the dietary life, the number of cases in which cardiovascular diseases are merged in non-cardiac surgery is increasing year by year.Many of the abdominal aortic aneurysms are asymptomatic and it is not uncommon to be discovered accidentally in preoperative examination of non-cardiac surgery.When gastrointestinal surgery involves malignant diseases of the gastrointestinal tract and abdominal aortic aneurysm, the two life prognosis-related diseases are merged, depending on the severity and urgency of the disease for each case, its treatment to determine the priority order.Abdominal aortic aneurysm occurred at the time of malignant disease surgery in 14 cases of gastrointestinal cancer patients who underwent surgery at the department during the 5 years from 2012 to 2016.T he actual condition of treatment for these cases was investigated.