Alloimmunization to erythrocyte antigens, of variable clinical significance, is a frequent finding in multitransfused patients. The incidence of such antibodies is 10-30%. Such antibodies are usually responsible for delayed hemolytic transfusion reaction, with the resulting destruction of the transfused red cells. The aim of this work was to screen for alloantibodies against red cell antigens and to identify these antibodies using the “Gel test” (DiaMed-ID microtyping system). Our study included 54 multitransfused patients (51 patients were thalassemic, two patients were haemophilic and one patient was with pure red cell aplasia). They were 27 males and 27 females with mean age of 10 years. The patients were tested within one week post transfusion and were subjected to the following investigations: •Routine laboratory tests including HB%, Reticulocyte count, ABO grouping and Rh phenotyping.•Screening test with Diacell I, II, and III with different techniques as LISS, enzyme and cold methods to detect large variety of antibodies.•Identification test with Dia-panel to choose the most specific antibodies present in the patient’s serum.5 cases out of the 54 patients gave positive results and showed antibodies against the different red cell antigens, with the percentage of alloimmunization to red cell antigens 9.2%. The antibodies detected were: anti-C, anti-E, anti-K, anti-CW, anti-e and anti-M, i.e. antibodies to Rh system antigens and to Kell antigen were detected most frequently (which reflects the greater immunogenicity of these red cell antigens). While the most common red cell alloantibodies in transfused sickle cell patients were anti-K, E, C, Jka, Fya and anti-M. According to these results, current guidelines for matching by ABO, Rh and Kell systems compared to blood phenotypically matched for the standard ABO-D is to be effective in preventing alloimmunization in patients with thalassemia. Extended matching for Duffy antigen system for patients with SCD is particularly important.