Currently accurate test for identification of HCV infection is not yet developed. We examined 1) the relationship between the result of anti-HCV by 3rd generation ELISA (ELISA/3) and of HCV-RNA by PCR from pre-transplant stored serum in 89 living donor renal transplant recipients and 2) the correlation between the result of each or combined tests and the development of post-transplant liver dysfunction (LDF). LDF was defined as the increment of serum transaminase over 100 1.U./ml in two consecutive tests. Patients with climically or biopsy proven LDF by cyclosporine were excluded. Pre-transplant HCV infection rate sed by ELISA/3 and PCR was 20.2 and 29.2% respectively. Patients with PCR (+) developed LDF frequently comparesd with negative partners (50 vs. 27%, p=0.0367). Significant disparity between ELISA/3 and PCR was present. In 71 ELISA/3 (-) patients, 16(22.5%) were positive for PCR. However 8 (44.4%) were negative for PCR in 18 ELISA/3 (+) patients. ELISA/3 (+) or PCR (+) patients developed LDF frequently rather than ELISA/3 (-)/PCR(- ) ones(50.0 vs. 23.6%, p=0.0106). We could explain these data with S possibilities, 1) end-stage renal failure patients had a blunt antibody production, 2) serum sample may be collected during the window period for antibody formation, 3) even ELISA/3 could not detect fine molecular response during the early HCV infection(false negative), 4) significant false positive or serum contamination in PCR test, and finally 5) self-clearing of HCV antigen may be present in the body. In conclusion, HCV detection by PCR method and antibody test by ELISA/3 must be complementary for the accurate evaluation of HCV infection during the recipient evaluation and posttransplantation follow-up period.