Objective: Myocardial infarction (MI) carries a strong risk of death and the development of major adverse cardiovascular events (MACE). A number of biomarkers have been proposed for risk stratification among patients with MI. The aim of this study was to determine whether elevated galectin-3 and midregional-pro atrial natriuretic peptide (MR-proANP) levels can be used as predictors of MACE in patients with acute myocardial infarction (AMI). Methods: Plasma levels of galectin-3 and MR-proANP were collected from 96 patients following their first AMI hospitalised in our clinic over the course of a year. Samples were taken on admission, and on the first and fifth day of hospitalization. During hospitalization, all patients were followed up for the occurrence of early major adverse cardiac events (MACE), defined as sudden cardiac arrest, new onset atrial fibrillation and need to use pressor amines. All patients were also followed up twelve months after AMI for the occurrence of late MACE defined as cardiac death, reinfarction and need for unscheduled PCI. Results: Patients who experienced early MACE had significantly higher galectin-3 and MR-proANP levels assessed on admission (p = 0.007, p = 0.003). ROC curve analysis found also galectin-3 concentration assessed on admission to be a strong predictor of late MACE (AUC = 0.75, p = 0.0061). MRproANP does not appear to have any value in predicting late MACE. Conclusions: A high concentration of galectin-3 and MR-proANP observed on admission in patients with acute myocardial infarction has significant prognostic value: it may identify patients at high risk of early adverse cardiac events after AMI. In contrast to MR-proANP, a high concentration of galectin-3 observed on admission may also identify patients at high risk of late MACE.