Objective: To evaluate the effectiveness and safety of anti-fibrinolytic therapy in on-pump coronary artery bypass grafting (CABG). Methods: Two hundred and eleven patients receiving on-pump CABG in Fuwai Hospital were recruited and randomized into treatment group (group T) and control group (group C) between October 2014 and February 2017. Tranexamic acid was given with a 10 mg/kg loading dose and 10 mg·kg(-1)·h(-1) infusion dose to group T and equal volume of saline was given to group C throughout the surgery. Postoperative drainage, allogeneic transfusion, complications, adverse events and mortality were recorded. Results: Patients of group T had less postoperative drainage [860 (670, 1 190)ml vs 985 (783, 1 365)ml], decreased red blood cell [2 (0, 8)U vs 6 (2, 10)U] and fresh frozen plasma [1 (0, 3) U vs 2 (0, 3)U] transfusion volume, lower fresh frozen plasma transfusion rate (53.33% vs 70.75%) than patients of group C (all P0.05). Conclusion: Tranexamic acid has definite anti-fibrinolytic effect, which can significantly reduce postoperative bleeding and allogeneic transfusion while no severe side effects were observed.