Congenital portosystemic shunt is a very rare congenital defect of the splanchnic venous system, in which blood from the portal vein completely or partially bypasses the liver. The most common symptoms are: hyperammonaemia (which may lead to encephalopathy), liver tumours, and hepatopulmonary syndrome. Due to its rarity and complex symptomatology it remains a great diagnostic challenge. Currently, endovascular closure of the shunt is a primary therapy. However, in cases where it is impossible, surgical ligation is an alternative. In selected cases liver transplantation may be indicated.