In order to investigate the applicability of liver transplantation after warm ischemia, a partial auxiliary auto-transplantation of the liver after 30 min of warm ischemia was carried out in 9 mongrel dogs. Among them, 6 dogs survived longer than 7 days. Liver functions, blood coagulability and histological changes were investigated before and after the transplantation. Serum GOT, LDH, and GPT levels were elevated immediately after transplantation, and returned to normal within a few days. Hemostatic tests also showed significant abnormalities after transplantation. Although PT and thrombotest became normal within a week, PTT and antithrombin III remained slightly abnormal for longer periods. Microscopically, vacuolization and degeneration of hepatocytes were observed after transplantation but they recovered completely within 4 weeks. Based on these results, it could be said that the livers subjected to warm ischemia for 30 min ischemia were still acceptable for auxiliary transplantation.