BACKGROUND: Acute myocardial infarction is one of the most common causes of death in developed countries. Previous studies have shown that women experience higher mortality in the period following acute myocardial infarction. It is still not clear whether this is due to higher average age of female patients or due to other causes. ----- OBJECTIVE: To determine the association of female sex to mortality after acute myocardial infarction during 36-48 months of follow-up. ----- PATIENTS AND METHODS: This study used patient data from the MIRCO registry (Myocardial Infarction Registry of Comorbidities and Outcomes) of patients who were treated for acute myocardial infarction in University Hospital Centre Sestre milosrdnice. For this study we used patient data from the year 2015. ----- RESULTS: Among 451 patients with acute myocardial infarction, 320 (71%) were male and 131 (29%) were female. The average age of male and female patients was 63 and 73, respectively. Male patients were more likely to smoke, be overweight and have hyperlipidemia. Female patients had higher average glucose blood levels on admission (all p<0.05). The survival rate during follow-up was 85.0% for male patients and 77.1% for female patients. Kaplan-Meier curves showed that female patients had significantly higher mortality than male patients. However, after using multivariate Cox regression to account for the higher average age of women, the difference became statistically insignificant (HR=1.50 [0.92-2.45], p=0.104). ----- CONCLUSION: Women have a lower incidence of acute myocardial infarction than men. However, in the following years they have a significantly higher mortality rate. This difference can be explained by the higher average age of female patients. To further study this difference, larger and multicentric studies should be done.