Abstract: Objective To determine the effect of tranexamic acid (TXA) after cardiopulmonary bypass (CPB) on the outcomes of cardiac surgery patients. Methods This retrospective study included adult patients (≥ 18 years old) who underwent elective valve replace surgery and/or coronary artery bypass surgery (CABG) with CPB from July 1, 2011 to December 31, 2016 in West China Hospital of Sichuan University. The patients were divided into TXA group (n=2 062), who received TXA after CPB, and the control group (n=4 236), who did not receive any TXA at all. The differences in postoperative complications such as death, excessive bleeding, ischemic event and bleeding related event, ICU and hospitality duration of the two groups were analyzed. Logistic regression analysis was performed to examine the effects of TXA on the outcomes of the patients. Results The rate of excessive bleeding and the median chest tube drainage of TXA group were less than those of control group (P<0.05), while the incidences of death, ischemic event and bleeding related event were comparable between the two groups (P>0.05). Multivariable regression analysis showed TXA after CPB was associated with the reduced risks of excessive bleedingodds ratio (OR):0.55, 95%confidence interval (CI):0.49-0.62, P<0.001 and death (OR:0.55, 95%CI:0.30-0.98, P=0.044), but was not associated with ischemic event and bleeding related event. Conclusion TXA after CPB following cardiac surgery could reduce the risk of excessive bleeding and death without increase of ischemic event.