Allogeneic red blood cell (RBC) transfusions and the use of reusable dialyzers sterilized with formaldehyde can lead to RBC alloimmunization in chronic hemodialysis patients. The formed RBC alloantibodies have been implicated in immediate kidney allograft failure and decreased RBC survival observed in these patients. Using indirect antiglobulin test, direct antiglobulin test (DAT), and direct Polibrene test (DPT), we detected an RBC alloimmunization rate of 17.2% (11/64) in transfused hemodialysis patients, and found the presence of anti-N-like and anti-Form antibodies in 5 (5.7%) and 53 (60.9%) individuals, respectively. The sensitivity rate of the DPT was significantly higher than that of the DAT in detecting anti-Form, but the DAT showed a higher specificity rate compared with the DPT. We conclude that patients treated with reusable dialyzers sterilized with formaldehyde may develop specific RBC alloantibodies that could increase the potential risk of hemolysis, decrease survival of RBCs, and increase the need of blood supply.