The diagnosis of hepatitis B is as follows: 1. epidemiological investigation: whether the patient has a history of hepatitis B exposure, such as whether blood transfusion, etc.; 2. clinical manifestations: including physical discomfort, loss of appetite, fatigue, etc. Some patients may have jaundice; 3. laboratory tests: divided into two aspects, mainly check the five items of hepatitis B and the DNA of hepatitis B virus, if both are positive, it means that the patient has hepatitis B virus infection. If you want to clarify whether the hepatitis B virus infection causes liver inflammation, it is recommended that liver function tests, such as transaminases, jaundice, protein metabolism and other laboratory tests be performed. Ultrasound can also be used to observe whether there are substantial changes in the liver, inflammatory changes, envelope condition, size of the spleen, and the presence of ascites.