A 11 year-old boy with no relevant past cardiac history presented with complain of chest pain last 10 days . Electrocardiography showed sinus rhythm incomplete RBBB with no ST –T changes at rest ,Subsequent echo revealed abnormal origin of RCA with normal systolic and diastolic biventricular functions, CT- Coronary angiography finally confirmed the diagnosis and showed abnormal origin of right coronary artery that arose from the left coronary sinus- that has been associated with angina, myocardial infarction, and sudden cardiac death. The incidence of coronary anomalies in patients undergoing coronary angiography varies from 0.64% to 1.3%. Many of these anomalies are clinically benign; however, others are associated with serious morbidity6. We describe the case of a patient in whom evaluation of chest pain revealed an anomalous right coronary artery arising from the left coronary sinus. We discuss the clinical importance of this anomaly and review the literature concerning current views and therapy.