Objective To investigate the effect of the clinical features，high-risk factors，and treatment regimens of transplantation-associated thrombotic microangiopathy（TA-TMA） on the early diagnosis and treatment outcome of TA-TMA. Methods A total of 40 patients with TA-TMA who were diagnosed in Hematology Medical Center，The Second Affiliated Hospital of Army Medical University，from January 2019 to June 2023 were enrolled as subjects，and 120 patients who did not experience TA-TMA after allogeneic hematopoietic stem cell transplantation during the same period of time were also enrolled. A retrospective analysis was performed for the clinical features，high-risk factors，treatment response，and survival status of TA-TMA patients. Results The binary logistic regression analysis showed that haploidentical transplantation，cytomegalovirus infection，acute graft-versus-host disease，and increased concentrations of calcium regulatory inhibitors were high-risk factors for TA-TMA（P<0.05）. According to the treatment regimen，40 patients with TA-TMA were divided into regimen 1 group with 26 patients（with the treatment regimen of plasma exchange） and regimen 2 group with 14 patients（without the treatment regimen of plasma exchange）. The results showed the survival of 8 patients in the regimen 1 group（30.8%） and 2 patients in the regimen 2 group（14.3%），and there was no significant difference in treatment outcome between the two groups（P>0.05）. Conclusion Haploidentical hematopoietic stem cell transplantation，cytomegalovirus infection，and acute graft-versus-host disease are high-risk factors for TA-TMA. The results of this study show no significant difference in treatment efficacy between the treatment regimens with or without plasma exchange. It is recommended to select treatment regimens according to the patient’s conditions and TA-TMA treatment guidelines，and it is urgent to further explore better treatment regimens to improve the prognosis and survival rate of TA-TMA patients.