PURPOSE: Coronary flow reserve (CFR) is recognized as an indicator of myocardial perfusion. The aim of this study was to assess the relationship between CFR in the non-infarcted myocardium and the incidence of major adverse cardiac events (MACEs). MATERIALS AND METHODS: 100 consecutive patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) were enrolled in the present study, and divided into MACE and non-MACE groups according to the incidence of 12-month MACEs. Left ventricular function and CFR were analyzed using two-dimensional echocardiography and myocardial contrast echocardiography at one week after PCI. Cardiac troponin I levels were assayed to estimate peak concentrations thereof. RESULTS: The MACE group was associated with lower CFR, compared to the non-MACE group (2.41 vs. 2.77, p < 0.001). In the multivariable model, CFR in the non-infarcted myocardium was an independent predictor of 12-month MACE (hazard ratio: 0.093, 95% confidence interval: 0.020–0.426, p=0.002) after adjustment for baseline demographic and clinical characteristics. CONCLUSION: CFR in the non-infarcted myocardium is a useful marker for predicting 12-month MACEs in patients with AMI undergoing primary PCI.