Anomalies of the left coronary artery are very rare, with an incidence range between .3% and 1.64%. The diagnosis is generally incidental during coronary angiogram, coronary artery bypass operation, or autopsy. However, sometimes this anomaly is not recognized during CABG operation and can be responsible for the recurrence of angina after CABG operation and even compromise the outcome. We presented a case in which the dual left anterior coronary artery from the right aortic sinus occasionally was shown in a coronary angiogram after CABG operation; the angiogram was performed because of the recurrence of angina.