A 41-year-old woman presented with complaints of increasing angina pectoris and coldness of her left arm for 1 month. Six months ago, she had undergone triple coronary artery bypass grafting (CABG) including left internal mammary artery (LIMA) to left anterior descending artery (LAD) and two saphenous vein grafts to the diagonal branch of LAD and obtuse marginal branch of the circumflex artery. Coronary angiography revealed that contrast media injected into the saphenous vein graft coursing down the diagonal branch flowed up to LAD and drained into the LIMA opacifying the left subclavian artery. Arch angiography documented a total occlusion of the left subclavian artery. A polytetrafluoroethylene graft was anastomosed between the left common carotid and axillary artery. After operation, the symptoms disappeared and blood pressure in her left arm recovered. This complication could be prevented by identification of subclavian artery stenosis during coronary angiogram or CABG. This study may suggest that subclavian artery angiography should be performed in patients who will undergo CABG even for a young woman such as our case.