Introduction. The number of patients with metabolic syndrome (MS) has been increasing recently. The development of MS can accelerate the progression of cardiovascular disease; and such patients have an increased risk of cardiovascular events, including sudden cardiac death. MS also adversely affects the course of acute coronary syndrome (ACS) and contributes to the development of myocardial infarction (MI) in these patients. Purpose. The aim of the study was to evaluate gender-related features of the development of MI in patients with ACS and MS. Materials and methods. 50 patients were included in the study. Patients were divided into two groups: men (n=25) and women (n=25) with MS, who were urgently hospitalized with ST-elevation ACS. All patients were examined for anamnesis data, clinical, biochemical blood tests and blood clotting tests, blood pressure (BP) levels, and electrocardiogram (ECG) data. Results and discussion. The mean age was 56.9±9.4 years in the group of men and 67.4±7.3 years in the group of women; women were significantly older than men (p<0.05). The body weight was not significantly different between the groups: 89.9±10.4 kg in the group of men and 90.3±8.7 kg in the group of women (p>0.05). Arterial hypertension was found in 88% of male patients and in 92% of female patients. There were no differences in its frequency and in the levels of blood pressure between the groups (p>0.05). Type 2 diabetes mellitus was significantly more prevalent in women with MS (p<0.05). Elevated levels of C-reactive protein (CRP) were found in 64% of men and 72% of women. The increase of CK-MB level was observed in 48% of men and 64% of women. The increase of CRP level in patients with MS was associated with hyperglycemia. Both in men and women with ACS, 4-component MS was more common than 3-component MS. Women with ACS and MS were more inclined to have the increased levels of troponin and to develop MI. Posterior localization of MI was more common in male patients, while anterior MI was more common in female patients. Conclusion. The study demonstrated the composition of MS in patients with ACS and gender-related features of MI development in this group of patients.