Background: Alloantibodies are antibodies that are produced in response to foreign antigens, the main stimuli responsible for erythrocyte alloantibodies in healthy adult donors are previous pregnancies and transfusions. Red blood cell (RBC) alloantibodies, especially IgG class, are clinically significant because of the association with hemolytic disease of newborns (HDN), hemolytic transfusion reaction (HTR) and a significant reduction in lifespan of transfused red blood cells. It has been stated that hemolytic reactions due to erythrocyte alloantibodies in donor blood is a relatively rare occurrence; however, they can occasionally cause severe transfusion reaction, particularly if given to infants and in the setting of massive transfusion. Objective: We aimed in this study to screen healthy Egyptian blood donors for the presence of red blood cells alloantibodies in a trial to prevent complications of blood transfusion, other secondary possible outcomes are to reveal the differential frequency of these alloantibodies among donors with previous blood transfusion, multiple pregnancies, different age groups and gender. Subjects and Methods: This study was carried out on 200 healthy Egyptian blood donors coming to Ain Shams University Hospitals Blood Banks. Data was collected on: gender, age, frequent donor or first time to donate, history of previous blood transfusion, number of pregnancies (in female donors), history of hepatitis or other viral infection, history of diabetes mellitus, hypertension, and history of recent surgery. Results: Sera from donors was subjected to alloantibody screening by manufacturer's antibody screening cells (Grifols I+II+III), when positive screening test, alloantibodies identification was done by manufacturer's antibody identification panel (Grifols), which consists of 11 panels. Out of the 200 donors, alloantibodies were detected in 8 donors (4%), a percent which is higher than other studies, may be due to the smaller sample size, alloantibodies were: anti-Kell in 1 case (12.5%), anti-M in 1 case (12.5%), and anti-C in 1 case (12.5%), anti-c in 1 case (12.5%), and anti P in 1 case (12.5%), and 3 (37.5%) cases were non-specific antibodies, 130(65%) of donors were males and 70 (35%) were females with a male to female ratio 1.8:1, their ages ranged from 19 years to 65 years with median of 32 years. Conclusion: Relation between alloantibodies and gender, multipara, repeated blood transfusion and previous surgeries was done showing statistically significance of previous surgeries and presence of allo-antibodies.