Ischemic colitis is a common type of intestinal ischemia, and coronary artery disease is often present in patients with this condition. We report on a 52 year-old man who presented with left lower abdominal cramping pain after eating, followed by several loose stools with fresh blood. Ischemic colitis was suspected on colonoscopy. Multi-slice computed tomography revealed calcified lesions and 50-70% stenosis in the proximal segment of the right coronary artery. A treadmill exercise test also was positive for ischemia. Coronary artery disease was diagnosed.