Immune hemolytic anemia in patients after organ transplantation has been reported generally to be graft-cell-derived due to elaboration by the donor's "passenger" lymphocytes of the antibodies directed against the recipient's red cell antigens. In contrast, this report presents a case that illustrates postoperative red cell alloantibody production by the recipient of an orthotopic liver transplant. Anti-Jka, -c, and -S, detected in the recipient's serum 9 days after transplantation, resulted in significant hemolysis. These alloantibodies had not been present in the recipient's serum before transplantation or in the sera of the liver or blood donors. In addition, anti-Jka and -c were eluted from posttransfusion red cells. The patient was transfused during surgery with crossmatch-compatible blood, that carried the alloantigens Jka, c, and S. The liver donor's red cells also carried the Jka, c, and S antigens. The recipient's pretransplantation red cell phenotyping was Jk(a-), c-, S-. The recipient had received only one transfusion 10 years prior to this operation, after which time he was noted to have anti-K. Immunosuppression initially consisted of cyclosporine, azathioprine, and prednisolone. This is believed to be the first report of delayed immune hemolysis due to non-ABO antibodies in a liver transplant patient treated with cyclosporine.