Abstract: Objective To explore the influence on the cellular immunity after Adefovir dipivoxil therapy by observing the levels of and the ratio of Th1 to Th2 in different time of patients with HBeAg-positive chronic hepatitis B.Methods Serial sera of 30 patients before and ADV therapy were collected, among which there 14 complete responding cases, 16 non-complete responding cases and 10 healthy people.The level of INF-γ and IL-4 were detected.Results The level of INF-γ of complete responding group in different time is significantly higher than that of control group (P<0.05) and partial responding group (P<0.05) .The level of IL-4 of complete responding group after treatment decreased while the partial responding group didn't.After treatment the ratio of Th1 and Th2 increased in both groups, of which the complete responding group had a significant increasing level.Conclusion The cellular immune response of patients with hepatitis B was resumed in some extent after ADV therapy.