Alveolar hydatid disease in man is the intermediate stage in the life cycle of the tapeworm Echinococcus multilocularis. This is a rare disease restricted to very few areas of the world. The occurrence of this disease in India is now described for (so far as the authors are aware) the first time. Some unusual features of the disease are highlighted in this patient. The hepatic lesion had infiltrated into the right atrial wall resembling an atrial tumour. The ostium of the inferior vena cava was occluded, causing Budd-Chiari syndrome. The radiological and haemodynamic study of the hepatic outflow tract in this disease are documented.