When coronary artery bypass grafting (CABG) is to be done, we use the internal thoracic artery (ITA) as a graft conduit in order to obtain longer patency. When the ITA acts as a good collateral to the lower extremities, blood flow to the extremities may decrease after CABG with ITA. Simultaneous open heart surgery and laparotomy may cause pulmonary complication. We made an algorithm of treatment for patients with coronary artery disease (CAD) and aortoiliac occlusive disease including these problems. From July 1991 to March 1992, 6 patients were operated and reviewed. Four patients were operated on for CAD and AIOD simultaneously. Two patients were operated on for CAD or AIOD at first and for the other secondarily. All 6 cases were discharged without any complications and are now free from angina and intermittent claudication. When the therapeutic plan for the patients with CAD and AIOD is made, it is very important that coronary revascularization is planned at first with careful evaluation of the blood flow to the lower extremities in cases with AIOD.