The study aims to demonstrate that antiviral therapy for patients with immune tolerance of CHB. On the basis of the original antiviral therapy of entecavir, further clarify the safety and effectiveness of entecavir combined with tenofovir amibufenamide.The investigators plan to enroll about 328 hepatitis B patients,. who are in the stage of immune tolerance. These participants will be devided into two groups randomly .Group A will receive the treatment of entecavir. Group B will be treated with entecavir and tenofovir amibufenamide. The participants in both groups will be followed up for 96 weeks.

The primary endpoint is to compare the inhibition rate of HBV-DNA between two groups. The secondary endpoint includes: (1) Comparing the decrease of HBV DNA at 48 weeks between the two groups. (2) Comparing the HBeAg seroconversion rates at 48 weeks and 96 weeks between the two groups. (3) The changes of HBsAg at 48 weeks and 96 weeks between the two groups. (4) Comparing adverse side effects between the two groups.

High HBV DNA level is an independent risk factor for liver cirrhosis and liver cancer, we know all patients with chronic hepatitis B virus infection in immune tolerance period had high viral load. So it is necessary to implement antiviral therapy for patients with chronic hepatitis B virus infection in immune tolerance period.Previous studies have found that combination of two antiviral drugs has a higher virological inhibition rate in patients with high viral load than single drug. Hence, the investigators' hypothesis is that treatment of patients with chronic hepatitis B virus infection in immune tolerance period result in higher virological inhibition rate and reduce of the risk of cirrhosis and liver cancer.

The investigators plan to enroll about 328 hepatitis B patients, who are in the stage of immune tolerance. These participants will be devided into 2 groups.Group A will receive the treatment of entecavir . Group B will be treated with entecavir and tenofovir amibufenamide. The participants in both groups will be followed up for 96 weeks. Unless there are serious adverse drug reactions, the protocol cannot be adjusted within 96 weeks.

The primary endpoint is to compare the inhibition rate of HBV-DNA between two groups. The secondary endpoint includes: (1) Comparing the decrease of HBV DNA at 48 weeks between the two groups. (2) Comparing the HBeAg seroconversion rates at 48 weeks and 96 weeks between the two groups. (3) The changes of HBsAg at 48 weeks and 96 weeks between the two groups. (4) Comparing adverse side effects between the two groups.

Inclusion Criteria:

1. Age between 18-65 years old;
2. HBsAg positive >6 months, HBsAg>1*10e4IU/ml;
3. HBV-DNA> 2 * 10e7IU / ml;
4. HBeAg positive;
5. ALT / AST remained normal which were followed up twice within 1 year with at least a 6-month interval each time.
6. No antiviral treatment with interferon or nucleoside (acid) analogues in the previous year

Exclusion Criteria:

1. infection with hepatitis A, C, D, E viruses or HIV infection ;
2. Combined with diabetes, hypertension, renal insufficiency, autoimmune diseases and other organ dysfunction And malignant tumors;
3. Patients using Immunosuppressive therapy or radiotherapy / chemotherapy for other diseases;
4. Patients with liver fibrosis, cirrhosis (FibroScan > = 9.4kpa) and liver cancer were identified;
5. Extrahepatic manifestations related to HBV (glomerulonephritis, vasculitis, nodular polyarteritis, peripheral neuropathy, etc.);
6. Allergic to nucleoside drugs
7. Pregnancy or having pregnancy plan within 2 years and Lactating patients;
8. Patients who are unable to comply with the arrange ment of this study or sign the informed consent.
9. Failed to return to hospital regularly for follow-up ac- cording to the study plan.
10. Researchers determine other condition that does not fit into the study.