Congenital biliary atresia associated with preduodenal portal vein in a 81-day-old girl is reported. Preduodenal location of the portal vein is a rare congenital anomaly which is frequently associated with various visceral anomalies, but its association with biliary atresia is relatively rare.Twenty-five cases of this combination were found in eighty-four preduodenal portal veins reported in the world literature including our case. In the case of preduodenal portal vein, anatomical relationship between the portal vein and the extrahepatic biliary tract in the porta hepatis might be changed; the biliary tract frequently locates posteriorly to the portal vein and enters the liver in the posterior position of the porta hepatis. A careful investigation and dissection of the proper porta hepatis should be necessary being kept in mind of this possibility in congenital biliary atresia associated with preduodenal portal
