Jehovah`s Witnesses who require cardiac operations represent a challenge to surgeon because of the patients` refusal to accept blood transfusion, We report a 6 year period, ending May, 1991 with a consecutive series of 25 Jehovah`s witnesses. Patients ranged in age from 11 months to 61 years. All operations were performed during cardiopulmonary bypass with bloodless priming, No patient received any blood or blood products during hospitalization. Perioperative mortality was 2 paients[8%]. We conclude that if we performed the cardiac surgery with careful operative technique and various blood conserving procedures, we can do the bloodless open heart surgery with relatively safety.