Ovarian cancer is a highly malignant neoplasm with high mortality rates. Research to identify markers facilitating early detection has been pursued for many years. Currently, diagnosis is based on the CA 125 and HE4 markers, as well as the ROMA algorithm. The search continues for new proteins that meet the criteria of good markers A total of 90 patients were included in the present study, allocated into: group 1, ovarian cancer, with 29 patients; group 2, endometrial cysts, with 30s; and group 3, simple ovarian cysts, with 31. Following histopathological verification, the CA 125, HE4, and metalloproteinase 3 (MMP3) levels were determined and the ROMA algorithm was calculated for all patients. The mean concentrations of all determined proteins, CA 125, HE4, and MMP3, as well as the ROMA values, were significantly higher in group 1 (ovarian cancer) compared to group 3 (simple ovarian cysts). The highest significant differences for the CA 125 levels (p<0.000001) and ROMA (p<0.000001) values were observed in postmenopausal women. For HE4, statistical significance was at the level of p=0.00001 compared to p=0.002 for MMP3. For the differentiation between ovarian cancer and endometrial cysts, the respective AUC ratios were obtained for CA 125, HE4, and MMP3 levels, as well as the ROMA values ( 0,93 / 0,96 / 0,75 / 0,98). After removing the post-menopausal patients, the MMP3 AUC value for ovarian cancer vs. benign ovarian cysts increased to 0.814. For post-menopausal women, the MMP3 AUC value for ovarian cancer vs. endometrial cysts was 0.843. As suggested by the results above, both the CA 125 and HE4 markers, as well as the ROMA algorithm, meet the criteria of a good diagnostic test for ovarian cancer. MMP3 seems to meet the criteria of a good diagnostic test, particularly in postmenopausal women; however, it is not superior to the tests used to date.