A case of spasm of saphenous vein aortocoronary bypass graft in a 70-year-old man is reported. Six months after coronary artery bypass grafting for three vessel disease, routine coronary angiography revealed narrowings of RCA just distal to the site of graft insertion and midportion of vein graft for right coronary artery. PTCA was performed for these stenoses, and then spasm of the vein graft occurred in other 2 points. Isosorbide dinitrate administration and balloon angioplasty for spastic parts were tried. No spastic narrowing of the vein graft was seen in angiography on the next day.