BACKGROUND:: Transfusion of blood products is often necessary for patients undergoing hematopoietic stem cell transplantation (HSCT). The need for red cell and platelet transfusion may vary significantly depending on the type of transplantation and underlying disease. OBJECTIVE:: To evaluate the need and volume of transfusions in patients undergoing HSCT in Zhongshan Hospital of Sun Yat-sen University. METHODS:: Retrospective data were collected on all patients undergoing autologous and allogeneic transplantation in our hospital during January 2004 to June 2010, regarding indications for transplantation, type of HSCT, CD34 stem cell dose, total number of red cell and platelet units transfused, cost, and times to achieve freedom from transfusion (FFT) and engraftment for white blood cell and platelet. The trigger for red cell transfusion was hemoglobin lower than 70 g/L. Platelet count less than 20×10/L was the trigger for platelet transfusion. We evaluated the needs, doses as well as cost for red cell and platelet transfusion for patients undergoing HSCT. Also, overall and disease free survival were analyzed as clinical outcomes. RESULTS AND CONCLUSION:: A total of 14 (93%) out of 15 patients undergoing autologous HSCT and 35 (90%) out of 39 patients with allogeneic HSCT exhibited total hematopoietic engraftment and FFT. Time to achieve FFT (median; range) for red blood cell units for autologous HSCT (14.6, 0-62) was significantly shorter compared with allogeneic HSCT (11.8, 0-108.5). Number of red blood cell units (median; range) transfused were significantly less in patients undergoing autologous HSCT (5.8, 0-35.5) compared to patients undergoing allogeneic HSCT (11.8, 0-108.5). The median cost of RBC transfusion was significantly higher in patients undergoing allogeneic HSCT compared to patients undergoing autologous HSCT. Transfusion of blood products is an expensive but integral part of HSCT, the more transfusion requirements for allogeneic HSCT than for patients undergoing autologous HSCT. FFT is a desirable long-term goal of successful HSCT.Song K, Qiu DF, Guo ZW, He HQ, Jian L, Huang GN, Huang GY, Liu AL, Xu XJ. Transfusion support therapy for patients undergoing hematopoietic stem cell transplantation.Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu. 2011;15(19): 3513-3517. [http://www.crter.cn http://en.zglckf.com]