OBJECTIVE Hepatitis C virus (HCV) is prevalent in renal insufficient patients. The aim of the present study was to evaluate the efficacy and tolerability of pegylated interferon alpha-2a (peg-IFN-alpha-2a) among these patients. METHODS Among 437 patients within total hemodialysis population in hemodialysis units, in total 83 patients (19.0%) were anti-HCV positive and of these 83 patients, 33 (39.7%) were HCV-RNA positive. Treatment was initiated in 33 patients who had chronic HCV infection. All patients were found to be HCV-RNA positive. During treatment, peg-IFN-alpha-2a (40 kDa), 135 microg/week was used on these 33 patients. RESULTS Twenty-six (78.8%) of the 33 patients enrolled in the study completed the treatment. Two patients (6.0%) did not complete treatment because they had serious adverse events such as anemia and thrombocytopenia. At the onset of treatment, while all of 26 patients were HCV RNA positive, HCV RNA turned to negative in all 26 patients 3 months after treatment. CONCLUSIONS At the end of the study, peg-IFN-alpha-2a treatment of patients with chronic hepatitis C on maintenance hemodialysis may improve prognosis and their quality of life.