Background: Cytokines and chemokines are critical regulators of innate and adaptive immunities during viral infection. We examined innate and adaptive immune responses to hepatitis C virus (HCV) and hepatitis B virus (HBV) at baseline and against controls. Methods: Twenty-seven cytokines were evaluated before treatment in 27 patients with chronic hepatitis C(CHC) [genotype1 (n=20), genotype2 (n=7), HCVRNA 5.72IU/ml] and 12 chronic hepatitis B(CHB) [e-antigen (Ag) (+) (n=5), e-Ag (-) (n=7), HBVDNA 6.191.31Logcopies/ml] and against controls(n=5). Results: Th1 and Th2 cytokines were significantly higher (p<0.05) in CHB than in CHC. The levels of IL-IL10 in CHC and CHB, and IL15 in CHC(genotype2) and CHB were significantly lower (p<0.05) than in controls. The levels of CXCL8 in CHC and CHB, IL12 in CHC and CHB [e-Ag (-)] and CXCL10 in CHC and CHB were significantly higher (p<0.05) than in controls. IFN-γwas higher in CHB than in controls. Conclusion: Cytokines levels differed between CHB and CHC before treatment. Innate immune responses were impaired in CHB with HBeAg(-) and CHC, but not in CHB with HBeAg(+) with high viral loads. Adaptive immune responses were impaired in CHB and CHC and appear to reflect the distinct state of virus-host immune interactions between CHB and CHC.