Four cases of a rare congenital anomaly, preduodenal portal vein (PPV), are presented. Preduodenal portal vein is known to be frequently associated with other anomalies including intestinal malrotation, situs inversus, biliary atresia, and pancreatic, splenic, and cardiac anomalies. Of our four cases, three had azygos or hemiazygos continuation of the inferior vena cava and other anomalies. We want to call attention to association of azygos or hemiazygos continuation of inferior vena cava with PPV.