A 66-year-old man with a 45-month course of chronic inflammatory polyradiculoneuropathy developed a coagulopathy due to an antibody to factor VIII. Despite clinical improvement in the neurologic disease at the onset of the coagulation disorder, antibody to peripheral nerve myelin was demonstrated in high titer. Antibodies to factor VIII and peripheral nerve myelin were both of the IgG class, but were immunologically distinct. This previously unreported association lends further credence to a disturbance in immunoregulation in chronic inflammatory polyradiculoneuropathy.