Aim To investigate the application opportunity of intra-aortic balloon pump （IABP） for patients with acute myocardial infarction （AMI） complicated by pump failure and its influence on therapeutic efficacy for these patients.Methods 85 patients with acute myocardial infarction complicated by pump failure were randomly divided into two groups according to application opportunity of IABP. Immediate IABP group （43 cases） underwent the IABP surgery immediately after diagnosis. Necessary IABP group （42 cases） after positive drugs therapy, whose systolic blood pressure remains ＜90 mmHg, underwent IABP surgery. And all the patients underwent emergency percutaneous coronary intervention （PCI） as soon as possible. The difference of door-to-balloon time, survival rate of the 1 week and 3 month postoperative in two groups were compared, left ventricular ejection fraction （EF） of 1 day and 3 month were measured. Results Door-to-balloon time of necessary IABP group was significantly greater than the immediate IABP group （96.7±31.2 min vs 78.3±35.6 min, P<0.05）. The survival rate of necessary IABP group after 3 months was significantly lower than a week postoperative （57.1% vs 69.0%）, and lower than instantly IABP group （57.1% vs 67.4%）, there were significant differences （P<0.05）. EF of two groups after three months were continuously decreased, the necessary IABP group declined more than the immediate IABP group （7.6%±3.5% vs 4.2%±3.1%, P<0.05）. Conclusion Early use of IABP for patients with acute myocardial infarction complicated by pump failure, can shorten revascularization time, reduce mortality and protect left ventricular systolic function.