Subclavian steal syndrome is understood to be an occlusion or stenosis of the subclavian artery proximal to the origin of the vertebral artery with a retrograde flow of blood through the ipsilateral vertebral artery. It is characterized most prominently and most consistently by unequal blood pressures of both arms. In this case, we found incidentally unequal arm pressures during emergence. After the surgery, the 95% stenosis of left anterior descending coronary artery and total occlusion of subclavian artery was proved angiographically. This patient had the risk factors of atherosclerosis such as male, DM, hypertension, smoking and hyperlipidemia. In conclusion, pressures should be taken from both arms during initial visit, when the patient has the risk factors of atherosclerosis.