Hepatitis B surface antigen is negative well. Hepatitis B virus is a DNA virus with an infectious agent. If you are not infected by the hepatitis B virus, you are negative for hepatitis B surface antigen, and conversely you are positive for hepatitis B surface antigen. Hepatitis B surface antigen negative patients have a lower risk of hepatitis, cirrhosis, and primary liver cancer. On the other hand, the risk of hepatitis, cirrhosis and primary liver cancer is significantly increased in hepatitis B surface antigen positive patients. 1. Hepatitis: Hepatitis B virus infection can be measured as hepatitis B surface antigen positive. Hepatitis B virus attacks hepatocytes, causing hepatocyte inflammation, edema, necrosis, causing hepatitis, leading to elevation of liver transaminases, bilirubin, etc., and manifesting abnormal liver function. 2. Cirrhosis: long-term hepatitis B virus infection, not standardized antiviral treatment, hepatocyte virus, inflammation stimulation, hepatocyte diffuse inflammation, fibrosis, pseudo lobar changes, resulting in cirrhosis. 3. Primary hepatocellular carcinoma: hepatitis B virus DNA sequence reintegrates with the infected host’s hepatocyte when it destroys, inactivating oncogenes and activating oncogenes, thus hepatocellular carcinoma occurs. At present, hepatitis B is a preventable and curable disease, early diagnosis and treatment can significantly slow down the development of the disease and improve the quality of life.