Advanced diagnostic systems and healthcare screening programs enabled increased diagnosis of congenital cardiovascular anomalies, including variations in coronary arteries. Single coronary artery is a rare congenital cardiovascular malformation in which all three main coronary arteries originate from a single coronary trunk. In this report, we present a patient with single coronary ostium giving rise to the left and right coronary artery systems, which was diagnosed incidentally with coronary computerized tomography and confirmed with conventional angiography. INTRODUCTION.