Results: 239 suitable blood units were selected to transfuse for 20 thalassemia and allogeneic blood stem cell transplantation patients, average blood units were selected for 1 patient were 11.9, especially 39 suitable blood units were selected to transfuse for 3 patients who had 8 antigens negative, 47 suitable blood units were selected to transfuse for 4 patients who had 9 antigens negative and 69 suitable blood units were selected to transfuse for 6 patients who had 10 antigens negative.