Matrix metalloproteinases play a key role in postinfarction remodeling of the heart. The aim was to study gender and age peculiarities of matrix metalloproteinases and their inhibitors, and determine their prognostic value in post-infarction aneurysm of the left ventricle formation. Methods and results. 76 patients with Q-wave myocardial infarction was studied by immunoassay analysis serum levels of matrix metalloproteinases and their inhibitors depending on patients sex and age. On the 1st day of the disease higher concentrations of MMP-9 and TIMP-1 were determined in women of elder age group. On the 10th day of the disease, in case of aneurysm formation, as in men, as women of any age, increasing of MMP-9 and decreasing of TIMP-1 levels was determined. Conclusion. Powerful prognostic potential of MMP-9 and TIMP-1 in post-infarction aneurysm formation was determined especially in women of elder age group.