There are about 30 million patients with chronic hepatitis B in China, and 20-30% of them will develop cirrhosis. For the treatment of chronic hepatitis B, China’s Guidelines for the Prevention and Treatment of Chronic Hepatitis B state that antiviral therapy is the key. Due to the lack of specific drugs for hepatitis B virus, the goal of antiviral treatment is to suppress the virus in the long term and reduce the occurrence of complications. Currently, anti-hepatitis B virus drugs can be divided into two main categories. One category is interferons; the other is nucleoside (acid) analogs. Interferon is divided into common interferon and pegylated interferon. Ordinary interferon, commonly used domestic interferon, needs to be injected every other day. The pegylated interferon is a long-acting interferon, which is injected once a week, and is currently used as an imported product. Interferon is suitable for HBV DNA-positive patients with 2 times normal < ALT < 10 times normal, and there are no contraindications to its application. Experts at home and abroad recommend interferon as the first choice for antiviral therapy for young and adolescent patients as long as they are eligible. Although interferon has disadvantages such as inconvenient application (requiring injection) and side effects. However, the advantages of interferon are also obvious: it can achieve more satisfactory results in a relatively limited course of treatment, and the results are often more stable. The course of interferon is usually about 1 year, usually observed for 4 months first and extended to 1 year if effective; if the application is not effective for 4 months, the drug is discontinued. The efficiency of regular interferon antiviral therapy is about 40%, while the efficiency of pegylated interferon can reach 50%. However, pegylated interferon is expensive, which discourages most patients from taking it. There are currently four nucleoside (acid) analogs. They are lamivudine, adefovir, telbivudine, and entecavir. The advantages of nucleoside (acid) analogs are that they are easy to administer and more potent. The disadvantage is that it is more difficult to stop the drug and requires long-term application. Since the drug has to be used for a long time, drug resistance is an issue of concern. Among the above four nucleoside (acid) analogues, entecavir has the strongest antiviral efficacy and the lowest incidence of drug resistance. Therefore, it can be the first choice in the application of nucleoside analogues. The problems are: ① Price. The monthly cost is about 1000 RMB, which is still unaffordable for numerous patients. ② Potential carcinogenic risk in long-term application. This point is based on the observation of large doses of entecavir applied in experimental animals, while no carcinogenic tendency has been found in clinical applications. Lamivudine has been used for more than 10 years, and its advantages and disadvantages have been very familiar. Its antiviral effect is strong, but it is prone to drug resistance, and the incidence of resistance reaches 50% after 3 years of application, and individual mutated strains of the virus can cause severe hepatitis. Tebivudine and lamivudine are structurally the same pyrimidine analogues, but their efficacy is stronger than that of lamivudine and resistance is lower than that of lamivudine. Adefovir is the least effective among the above four drugs and has a slow onset of action. The advantage is that the incidence of drug resistance is relatively low, with an incidence of resistance of about 20% after 3 years of application, and the genetic loci of resistance are different from those of lamivudine, telbivudine and entecavir, so that the drug can be replaced with adefovir after resistance to other drugs. From the perspective of clinical treatment, for patients who cannot apply entecavir, the initial treatment regimen can choose lamivudine + adefovir, which is guaranteed in terms of efficacy and prevention of drug resistance.