Postoperative acute renal failure is a frequent and serious medical complication following orthotopic liver transplant. Here, we report our experiences with liver transplant recipients who developed acute renal failure in the early period following orthotopic liver transplant. Among 100 liver transplants performed between April 1993 and January 2004, we retrospectively analyzed 91 patients (mean age, 29.9 +/- 14.0 years) who had undergone orthotopic liver transplant. The underlying causes of liver failure were cryptogenic liver cirrhosis (n=27), viral hepatitis (n= 21) (hepatitis-B-related liver cirrhosis [n=13], hepatitis-C-related liver cirrhosis [n=7], and hepatitis-B- and C-related liver cirrhosis [n=1]), autoimmune hepatitis (n=18), Wilson's disease (n=10), primary sclerosing cholangitis (n=8), biliary atresia (n=3), Budd-Chiari syndrome (n=2), and primary biliary cirrhosis (n=2). The immunosuppressive regimen included mycophenolate mofetil (azathioprine for 10 patients), cyclosporine, and steroids. Six patients received a combination of tacrolimus and steroids. Ten patients (10.9%) experienced acute renal failure, 7 (70%) were men, and none of them required renal replacement therapy and/or died. Four patients were diagnosed as having cryptogenic liver cirrhosis; 2 with hepatitis-C-related liver cirrhosis, 2 with autoimmune liver cirrhosis; 1 with primary biliary cirrhosis; and 1 hepatitis-B-related liver cirrhosis. Six patients were Child-Pugh's classification C, and the others were B. The rate of postoperative acute renal failure in our patients was relatively low when compared with other series, and our outcomes were good.