This is a prospective/retrospective, observational follow-up study of effects of fatty liver on chronic hepatitis B. Patients will join this study who undergo transient elastography with liver stiffness (LS) and CAP measurements or Ultrasonic examination. All recruited subjects will undergo comprehensive clinical, anthropometric and laboratory assessments at the time when transient elastography or Ultrasonic examination is performed. We plan to compare the relationship between chronic hepatitis B and non-alcoholic fatty liver disease. Patients will be divided into several groups based on the demand.