Two cases of portal hypertension due to hydatid cysts of the liver are reported. In one of the patients, symptoms were secondary to obstruction of inferior vena cava and hepatic outflow tract. The other patient was operated on with a diagnosis of extrahepatic presinusoidal portal hypertension caused by extrinsic compression of the liver by an hydatid cyst. Although hydatidosis is a benign disease, it can produce serious complications as in these reported cases. Therefore hydatidosis should be remembered amongst the causes of portal hypertension in countries where the disease is endemic.