The modified piggyback technique with side-to-side cavocavostomy decreases the risk of outflow obstruction compared with the standard piggyback method. However, this modification is not ideal for recipients who receive a graft that is voluminous or bears an enlarged caudate lobe.We modified the inferior vena cava (IVC) preservation technique against deleterious complications of compression by using a passing loop.A 49-year-old woman, who underwent orthotopic liver transplantation for hepatic failure, was allocated a large-size liver. In anticipation of serious caval compression due to the voluminous grafts, we kept the suprahepatic or infrahepatic donor caval cuffs open for an anastomosis. The first anastomosis was performed between suprahepatic donor IVC cuff and recipient middle-left hepatic vein common channel; the second anastomosis was a terminolateral cavocavostomy between infrahepatic donor IVC cuff and the anterior wall of the recipient's IVC.When the liver circulation was restored, the donor retrohepatic vena cava served as a passing loop for both hepatic venous outflow and infra-diaphragmatic venous return to bypass possible IVC compression. Our technique may solve a dilemna for patients receiving voluminous liver grafts.