Hepatitis B virus (HBV) infection may progress to liver failure and liver cancer, for this reason it is a serious health problem. The mechanisms of chronicity are poorly understood. The balances in cytokine production profiles may play a crucial role in determining the resolution or persistence of infection. In this study, we aimed to determine various cytokine levels in patients with chronic HBV infection and to reveal the relationship between levels of cytokines and different clinical phases. HBsAg positive patients with a duration of positivity longer than six months who applied to outpatient clinic of Infectious Diseases and Clinical Microbiology Department of Ankara Training and Research Hospital between October 2005 and June 2006 were included to the study. There were 57 patients in chronic hepatitis B group. There were 24 healthy individuals in the control group. Serum interleukin (IL)-6 and IL-10 levels were detected and compared between patients and controls. There were 25 chronic hepatitis and 32 inactive carrier patients in the patient group. Serum IL-6 levels in patients with chronic HBV infection (8.496 pg/mL) were higher than those of the control group (6.850 pg/mL) and the difference was statistically significant (p= 0.022). Serum IL-10 levels were 0.784 pg/mL and 0.052 pg/mL in patient and control groups, respectively. There was a statistically significant difference between these groups (p= 0.019). Correlation between serum alanin aminotransferase (ALT) levels and cytokine levels were also examined. There wasn’t any correlation between the levels of IL-6 and IL-10, and ALT in patients. As a conclusion, increased IL-10 levels may be associated with persistence of hepatitis B infection. Testing the level of serum IL-6 may be helpful to determine the liver inflammation in patients with chronic hepatitis B infection.