The content of matrix metalloproteinases 7 and 9 was significantly increased, while the content of metalloproteinase 2 was reduced in ovarian cancer tissue compared to benign tumors. In blood serum from patients with ovarian cancer, the concentrations of matrix metalloproteinases 7 and 9 and their type 1 tissue inhibitor were significantly elevated, while the concentration of matrix metalloproteinase 2 was reduced compared to the corresponding parameters in healthy women. After chemotherapy, tissue and serum concentrations of metalloproteinases and their inhibitor in patients practically returned to normal. A significant positive correlation between serum levels of matrix metalloproteinases 7 and 9 and tissue inhibitor of metalloproteinases-1 in patients with ovarian cancer and the size of primary tumor (ultrasound examination) and a positive correlation between these parameters and the concentration of classical ovarian cancer marker CA-125 were demonstrated.