Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 12 4 2018 05 30 321 327 EN Negin Shokrgozar School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran Gholamhossein Tamaddon Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran 2017 11 06 2018 05 30 Hematopoietic stem cell transplantation (HSCT) is a useful treatment. In contrast to solid organ transplantations, the use of ABO blood group mismatch is acceptable in HSCT. Immediate or late hemolytic reactions, pure red cell aplasia, delayed red blood cell recovery, and graft-versus -host disease are the results of this situation. This review shows the consequences of ABO-mismatched HSCT and its impacts on HSCT parameters, as well as providing clinical guides in this situation. https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/878 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/878/753