Objective To investigate the efficacy and safety of half-dose tirofiban, a platelet glycoprotein Ⅱb/Ⅲa receptor antagonist, in the elderly patients during preoperative transition period before receiving coronary artery bypass grafting. Methods A total of 117 patients [aged 60?75(67.76±3.07) years] with non-ST segment elevation acute coronary syndrome(NSTE-ACS) admitted to our hospital from January 2012 to December 2014 were enrolled in this study. All the patients were diagnosed as three-vessel disease and/or left main coronary diseases by coronary arteriography, and required surgical treatment of coronary artery bypass grafting (CABG). Upon termination of dual antiplatelet therapy, the cohort was randomly divided into half-dose tirofiban plus low molecular weight heparin (LMWH) group (group A, n＝60), and simple LMWH group (group B, n＝57). The patients of group A were subjected to half-dose tirofiban after coronary arteriography till 12h before the surgery and subcutaneous injection of LMWH till 24h before surgery. While those of group B only received subcutaneous injection of LMWH as in group A. Additionally, conventional medical treatment was also given to each patient. The following parameters were compared between the 2 groups, including baseline levels, bleeding, as well as major adverse cardiovascular events (MACE) during transition period, such as intractable angina, nonfatal myocardial infarction, malignant arrhythmia and cardiac death. Results No significant difference was found in the baseline data between the 2 groups (P＞0.05). For the MACEs, the incidence of intractable angina was lower in group A than in group B [33.3% (20/60) vs 57.9% (33/57), P＝0.01], and so were those of nonfatal myocardial infarction, malignant arrhythmia and cardiac death, though no significant difference was observed (P＞0.05). In group A, epistaxis (n＝1) and hemorrhoidal bleeding (n＝1) was noted, while in group B, 1 case with gum bleeding was seen. No statistical difference was observed in the amounts of bleeding during and after operation between the 2 groups [intra-operative: (564.17±125.58) vs (542.46±94.46)ml, P＝0.30; post-operative (4.63±1.40) vs (4.39±1.28)u; P＝0.32]. Conclusion Compared with simple LMWH, continued preoperative administration of half-dose tirofiban in combination with LMWH can effectively decrease the incidence of adverse cardiovascular events, but have no effect on the bleeding volume during peri-operative period in the elderly NSTE-ACS patients undergoing CABG.