This article focuses on autoimmune manifestations related to the hepatitis B virus (HBV). Although the HBV vaccination has resulted in the decline of the virus, approximately 400 million individuals are infected worldwide. Up to twenty percent of the afflicted may develop extrahepatic manifestations ranging from the severe polyarteritis nodosa to the many, varied, and less severe clinical and biologic forms. Currently, control of the viral infection is mainly based on the use of antiviral drugs (with the current availability of potent agents). Discussion of two hypotheses of the pathophysiology of the virus is followed by descriptions of the general, renal, rheumatologic, neurologic, skin, ophthalmologic, and hematologic manifestations.