Ten cases of intraoperative coronary artery spasm were reviewed retrospectively. Four cases were open heart surgeries, one was a surgery for aortic dissecting aneurysm, and the other five were abdominal ones. In the cases of open heart surgery under anesthesia with high dose fentanyl, coronary artery spasm occurred at weaning period from cardio-pulmonary bypass. In the cases of abdominal surgery, all under neuroleptanesthesia with continuous epidural block, coronary artery spasm occurred within one hour after the beginning or before the end of operation. In four of five abdominal surgeries, systolic blood pressure became less than 90 mmHg when coronary artery spasm occurred. Coronary artery spasm brought severe depression of myocardial contractility and life threatening arrhythmias by which weaning from cardiopulmonary bypass became difficult during open heart surgery. There was a case which required several hours before hemodynamics became stable also in abdominal surgery. It was suggested that general anesthesia with continuous epidural block could be a triggering factor of coronary artery spasm when hypotension and insufficient depth of general anesthesia are present simultaneously.