Previous studies in Caucasian patients showed treatment of chronic hepatitis C with pegylated interferon/ribavirin was well tolerated, and produced a higher response rate especially in genotype 1 infections. However, it is unknown whether this conclusion can be extrapolated to patients with Chinese ethnic origin. A total of 153 patients with biopsy-proven chronic hepatitis C were randomly assigned to receive either weekly injection of peginterferon alpha-2b 1.5 mcg/kg plus oral ribavirin (1000 or 1200 mg/day, depending on body weight) (PEG group, n = 76) or 3 MU of interferon alpha-2b t.i.w. plus ribavirin (IFN group, n = 77) for 24 weeks. Sustained virological response (SVR) was defined as the sustained disappearance of serum hepatitis C virus (HCV) RNA at 24 weeks after the end of treatment by polymerase chain reaction assay. Baseline demographic, viral and histological characteristics were comparable between the two groups. Using an intent-to-treat analysis, HCV genotype 1 patients showed a significantly higher SVR in patients receiving PEG-IFN rather than IFN (65.8%vs 41.0%, P = 0.019), but no difference was found in genotype non-1 patients (PEG vs IFN: 68.4%vs 86.8%, P = 0.060). Genotype 1 patients (28.6%) in the PEG-IFN group relapsed, as compared with 52.9% in the IFN group (P = 0.040). Multivariate analyses showed early virological response at week 12 of therapy and genotype non-1 were significant predictors to SVR. As compared with the IFN group, patients receiving PEG-IFN had a significantly higher rate of discontinuation, dose reduction, fever, headache, insomnia, leucopenia and thrombocytopenia. In genotype 1 chronic hepatitis C Chinese patient, PEG-IFNalpha2b ribavirin had significantly better SVR and lower relapse rate when compared to IFN/ribavirin. Both regimens can be recommended for genotype non-1 chronic hepatitis C Chinese patients. However, a higher rate of adverse events and discontinuance of therapy were noted in patients treated with PEG-IFNalpha2b ribavirin.