Objective To examine the effect and possible mechanism of Wuse Liuwei Decoction（ 五色六味方）treating chronic hepatitis B. Methods Seventy-eight patients with chronic hepatitis B were randomized into treatment group and control group

39 cases in each group. The control group was given lamivudine tablet 100 mg orally each time

once every day. In addition to the treatment of the control group

Wuse Liuwei Decoction granule was given to the treatment group

1 dose every day. Both groups were treated for 48 weeks. Hepatitis B Virus deoxyribonucleic acid（ HBV DNA） load and negative conversion rate

the level of peripheral blood interleukin 17（ IL-17） and forkhead box P3（ FOXP3）

as well as Th17 / Treg of patients was detected before treatment

at the 24 th and 48 th week of treatment. Results In the treatment group

HBV DNA negative conversion rate at the 24 th and 48 th week of treatment was 80. 77% and 92. 30% respectively

while that was 57. 70% and 69. 23% respectively in the control group.HBV DNA negative conversion rate in the treatment group at all time of treatment was higher than that in the control group（ P < 0. 05）. At the 48 th week of treatment

the level of IL-17 and FOXP3

as well as Th17 / Treg in both groups decreased compared with those before treatment（ P < 0. 05）. At the 24 th and 48 th week of treatment

the level of IL-17 and FOXP3

as well as Th17 / Treg in the treatment group were lower than those in the control group at the same time（ P < 0. 05）. Conclusion Wuse Liuwei Decoction combined with lamivudine tablet might reduce the liver inflammation of patients with chronic hepatitis B and enhance the antiviral effect. The mechanism might relate to regulating Th17 / Treg balance.