Abstract: AIM:To evaluate the efficacy and safety of prophylactic intra-aortic balloon pump (IABP) in the treatment of high-risk coronary artery disease (CAD). METHODS: Fifty-nine patients with high risk CAD were divided into two groups: trial group (prophylactic IABP, n=23) and control group (non-prophylactic IABP, n=36). IABP related complications, incidences of malignant arrhythmias, heart failure and cardiac shock, and incidence of major adverse cardiovascular events (MACE) were observed. RESULTS: In the IABP group and control group, no significant changes were observed in thrombocytopenia. The incidences of anemia, hypostatic pneumonia and embolism in the IABP group were significantly higher than those in non-IABP group (P<0.05) and the incidences of heart failure, cardiac shock and malignant arrhythmias in the IABP group were lower than those in non-IABP group (P<0.05). The death rate within a year in the IABP group was significantly lower than that in the non-IABP group (P<0.05). CONCLUSION: Prophylactic IABP in the treatment of high-risk CAD patients effectively improves hemodynamics, coronary perfusion and left ventricular functions and reduces the occurrence of heart failure, malignant arrhythmias and cardiac shock and thus significantly improves the survival rate within a year. IABP is one of the best assistive devices in the treatment of high-risk CAD patients.