Abstract: To evaluate the oxidative stress status and its clinical significance in patients with chronic hepatitis B. Methods: Total antioxidant response and malondialdehyde level were measured and oxidative stress index was calculated in 42 patients with chronic hepatitis B, 30 inactive carriers and 22 healthy controls. Results: Malondialdehyde (MDA) and oxidative stress index (OSI) were significantly higher in chronic hepatitis B patients than in inactive HbsAg carriers and controls（P＜0.05, P＜0.05，P＜0.01，P＜0.01）. Total antioxidant response was comparable in chronic hepatitis B subjects, inactive HbsAg carriers and controls (both P＞0.05). MDA and oxidative stress index were also comparable ininactive HBsAg carriers and controls (both P＞0.05). Serum alanine aminotransferase level was positively correlated with malondialdehyde concentration and oxidative stress index only in chronic hepatitis B subjects (r=0.61 and r=0.45, respectively), and there was no significant relationship between HBVDNA and oxidative stress. Conclusion: There are disturbances of oxidative stress and antioxidative

Key words: Hepatitis B, chronic, Oxidative stress, Malondialdehyde