Levoatrial cardinal vein (LACV) is anomalous connection between the left atrium or pulmonary veins and any systemic vein which is derived from cardinal venous system. Presence of the levoatrial cardinal vein without a cardiac anomaly is a very rare congenital anomaly of the systemic venous return. In the literature, no LACV anomaly was found in two siblings who were asymptomatic and did not have an additional cardiac anomaly. Therefore, we present two cases ( two siblings ) the symptoms, diagnosis (the echocardiographic finding, computed tomography (CT) and aniographic images ) and treatment modalities of isolated levoatrial cardinal vein.