Since January 1981, we have performed bypass surgery between the inferior vena cava and the right atrium (IVC-RA bypass) using ring-reenforced expanded polytetrafluoroethylene (EPTFE) graft in five cases of Budd-Chiari syndrome in which at least one or more hepatic veins or accessory hepatic veins connected with the inferior vena cava. IVC-RA bypass cases include two men and three women aged 33 to 61 years old. The EPTFE graft was cut just outside of the ring and anastomosed to the inferior vena cava and the right atrium. The ring was utilized to keep the anastomosed orifice circular. EPTFE grafts (14 to 16mm in diameter and 24 to 27cm in length) were placed through the route alongside the second portion of the duodenum behind the transverse colon and anterior to the liver. Warfarin was given as an anticoagulant for at least several months to several years postoperatively in 4 cases with life-long time in one case. The cases have been followed up for 4 to 24 years. Three patients showed good graft patency for 20 years or more after the operation. Two cases died of rupture of esophageal varices 12 and 23 years after the bypass surgery, respectively. IVC-RA bypass using ring-reenforced EPTFE graft for Budd-Chiari syndrome is expected to have good long term patency without long term anticoagulant therapy, but its effect on preventing the progress of liver cirrhosis and esophageal varices is limited. Therefore IVC-RA bypass is a choice, when direct reconstruction of the hepatic vein and the inferior vena cava is impossible.