OBJECTIVE： To observe the effects of different regimens of tranexamic acid on perioperative bleeding and postoperative compliance of simultaneous bilateral total knee arthroplasty（TKA）. METHODS： A total of 70 patients undergoing simultaneous bilateral TKA in our hospital were randomly divided into control group and observation group， with 35 cases in each group. Control group was given Tranexamic acid injection 15 mg/kg 30 min before surgery. Observation group was given Tranexamic acid injection 15 mg/kg， 30 min before surgery and 30 min before suturing incision. The operation duration，total blood loss，intraoperative blood loss， postoperative drainage as well as the levels of FIB， PT， APTT before trectment and 3 d after surgery，the occurrence of postoperative compliance and ADR were observed and compared between 2 groups. RESULTS： There was no statistical significance in operation duration， intraoperative blood loss and rate of ADR between 2 groups （P＞0.05）. The total blood loss， postoperative drainage and the incidence of complications of observation group were significantly lower than those of control group， with statistical significance （P＜0.05）. There was no statistical significance in coagulation indexes （FIB， PT and APTT） between 2 groups before treatment and 3 d after surgery， with statistical significance （P＞0.05）. CONCLUSIONS： The application of tranexamic acid 30 min before simultaneous bilateral TKA and 30 min before the end of surgery can reduce perioperative bleeding and postoperative venous thromboembolism with good safety.