The Budd-Chiari syndrome is a rare type of portal hypertension caused by complete or incomplete obstruction of the hepatic vein or the corresponding portion of the inferior vena cava or both. In this case, the obstruction was located just beneath the diaphragm, above the right hepatic vein opening, which was confirmed by vena cavography preoperatively. Budd-Chiari syndrome with stenosis or thrombosis of the inferior vena cava may be cured by prosthetic bypass to the right atrium. This case is caused by thrombus of unknowed primary origin. Combined mesoatrial and cavoatrial shunt should be encouraged in this specific situation. Postoperatively, there were marked fall of venous pressure and symptoms and signs improved remarkably.