Objective To investigate the clinical efficacy of preoperative therapeutic plasma exchange(TPE)in pre-venting acute rejection after ABO incompatible kidney transplantation(ABOi-KT).Methods Nine patients with ABOi-KT who were admitted to the renal transplant department of our hospital from April 2022 to April 2024 were retrospectively ana-lyzed.They received a total of 28 TPEs before kidney transplantation,and the treatment plan was summarized as follows:The proportion of the substitute fluid,as well as the frequency and volume of TPE were determined based on the patient′s ABO blood group system antibody titer,gender,height,weight,hematocrit and other indicators upon admission.The pa-tient′s relevant laboratory indicators,including hemoglobin,platelets,leukocytes,coagulation function,total protein,albu-min,globulin,A/G,creatinine and urea nitrogen upon admission and after TPE were monitored and statistically analyzed.After transplantation,changes in renal function indicators such as ABO blood group system antibody titers,creatinine and u-rinary excretion were observed,and clinical symptoms of acute rejection,such as swelling,pain and edema in the transplan-ted kidney area were observed.Results Nine ABOi-KT patients had an average of about 3 TPEs before transplantation sur-gery,with an average total volume of approximately 2 500 mL to 3 500 mL per TPE,or approximately about 1.01 to 1.16 plasma volume(PV).After multiple TPEs,pre-transplantation antibody titers decreased by an average of 3 times compared to before TPE.There were no statistically significant differences in Hb,PLT,PT,PTA,INR,TBil,ALB,Cr and BUN(P＞0.05),while statistically significant differences were found in WBC,APTT,Fbg,TP,GLB and A/G(P＜0.05).After surgery,the creatinine level of 9 patients dropped to approximately 100 to 140 μmol/L,the urine output was normal,and the urine protein dropped to weakly positive or negative values.None of the nine patients experienced acute rejection.Con-clusion TPE can effectively reduce the level of ABO blood group antibody and prevent the occurrence of acute rejection in ABOi-KT patients.