The authors examined an incidence of serum hepatitis among 62 patients who have received blood transfusion at the Hospital das Clinicas of F.M.U.F.Pe, Brazil. The examinations of the patients were performed once a month for six consecutive months after the blood transfusion. Among these patients, three cases (4.8%) were proved to be viral hepatitis (serum hepatitis based on clinical, laboratory data, and histopathological examinations).