AbstractCirculating immune complexes were isolated by conglutinin affinity chromatography during the course of hepatitis A virus infection in a chimpanzee. Characterization of circulating immune complexes showed that most of the hepatitis A virus‐specific antibody was IgM, that IgG was present and that C3d and fibronectin were also present. Hepatitis A virus capsid polypeptides were identified in the circulating immune complexes and polypeptides in the molecular weight range of 63 to 67 kDa having immunological determinants common to both C3d and hepatitis A virus. Hepatitis A virus‐RNA was detected in these circulating immune complexes using the polymerase chain reaction for in vitro amplification of nucleic acid and suggests the circulating immune complexes contain intact vi