Although the capacity for transmission of hepatitis B infection by semen is well recognized, the potential for transmission by artificial insemination remains theoretical. Currently, screening of semen donors for hepatitis B virus infection is not standard practice. We saw a case of acute viral hepatitis B in a woman following artificial insemination with semen from a donor subsequently found to be positive for hepatitis B surface antigen (HBsAg). Both the donor serum and semen contained HBsAg and hepatitis B e antigen, and the HBsAg subtype was identical to that of the patient. Documentation of hepatitis B virus transmission by artificial insemination indicates that HBsAg screening of semen donors should be routine practice.