We report a case of acute type I aortic dissection with ischemic enterocolitis due to blood flow insufficiency in the superior mesenteric artery. The patient was a 52-year-old man who visited the hospital with major complaints of sudden low back pain and melena. Mesenteric ischemia was suspected, and angiography revealed type I aortic dissection with accompanying blood flow insufficiency in the superior mesenteric artery. Because catheterization during angiography improved the blood flow disorder and prevented intestinal necrosis, it was possible to replace the ascending aorta with a prosthetic graft. Arterial pulsation in the mesentery was recovered by the operation and the patient's life was saved without bowel resection. This case demonstrates that prompt surgical or percutaneous relief of ischemia in major organs is important to save lives in the cases of acute aortic dissection with ischemic complications.