 This is an open label, randomized-controlled, comparative trial. HBV and HCV dually infected patients with negative hepatitis B e antigen HBeAg were enrolled in the study. The definition of HBV and HCV dual infection included seropositivity of HCV antibody anti-HCV and HBsAg for more than 6 months, together with positive serum HCV RNA. Eligible subjects were randomized into 2 groups at treatment initiation. Subjects who were randomized into the genotype guided therapy GGT group received Peg-IFN and standard dose RBV 1200 mgday for 48 weeks in subjects infected with HCV genotype 1 or Peg-IFN and low dose RBV 800 mgday for 24 weeks in subjects infected with HCV genotype 23; the patients were then followed for 6 months. For subjects who were randomized into the response guided therapy RGT group, the duration of Peg-IFN and RBV therapy was abbreviated to 24 weeks in subjects with HCV genotype 1, a pre-treatment low viral load LVL, 400000 IUmL and RVR defined asHCV RNA 50 IUmL at 4th week of therapy; the duration was 16 weeks in subjects with HCV genotype 23 and RVR. 