• A 61-year-old man was seen for Guillain-Barré syndrome (GBS) complicating acute type B hepatitis. Results of detailed electrophysiological studies were characteristic of a severe peripheral neuropathy of the segmental demyelinating type. Immunological studies demonstrated cell-mediated sensitization to peripheral nerve basic protein. Twenty-six cases of GBS complicating viral hepatitis were analyzed for age, sex, temporal relationship of the onset of the hepatitis to that of the polyneuritis, and outcome.