Objective    To evaluate the clinical efficacy of preoperative intra-aortic balloon pump (IABP) insertion in patients with off-pump coronary artery bypass grafting (OPCABG) surgery. Methods    The clinical data of 130 patients who underwent OPCABG with IABP from 2015 to 2019 in our hospital were retrospectively analyzed. The patients were divided into two groups, including a group A (preoperative IABP insertion, n=72) and a group B (emergent IABP insertion, n=58). There were 42 males and 30 females in the group A with an average age of 60-72 (65.0±5.2) years. There were 32 males and 26 females in the group B with an average age of 56-73 (62.3±7.6) years. The in-hospital mortality rate and prognosis were compared between the two groups. Results    The in-hospital mortality rate in the group A (4.2%) was significantly lower than that in the group B (12.1%, P=0.002). The IABP time (40.8±10.3 min vs. 65.3±15.6 min), mechanical ventilation time (18.7±6.1 min vs. 48.7±10.5 min) and ICU stay time (48.1±7.8 min vs. 90.2±21.3 min) of the group A were shorter than those of the group B (P<0.05). The number of bypass grafts was not significantly different between the two groups (3.6±1.2 vs. 3.8±1.0, P=0.387). Multivariable logistic regression analysis indicated that independent risk factors for in-hospital mortality included age [OR=1.04, 95%CI (1.01, 1.10), P=0.030], female [OR=2.56, 95%CI (1.53, 6.12), P=0.000] and left ventricular end-diastolic diameter [OR=1.05, 95%CI (1.01, 1.13), P=0.030]. Preoperative IABP support was the protective factor [OR=0.17, 95%CI (0.01, 0.78), P=0.005]. Conclusion    Patients undergoing OPCABG with preoperative IABP insertion may reduce in-hospital mortality rate and improve outcomes.