Adnexal masses are frequently found in both symptomatic and asymptomatic women. The frequency of them is 7,8% in reproductive aged women and 2,5-18% in postmenopausal patients. Aim: to investigate clinical significance of the Risk of Malignancy Index (RMI) and to compare it with histological findings in patients with adnexal masses. Patients and methods: 345 patients with adnexal masses were evaluated. Depending on the menopausal status, serum CA-125 level and ultrasonographic findings RMI scores were calculated for each of patients. Results: according to RMI all the patients were divided in to two groups: first group - 283 (62%) of patients with RMI less then 200 and the second group - 52 (38%) women with RMI more then 200. The patients of the second group were referred to the oncologist. Among the patients with RMI <200, 137 (48,4%) endometriomas, 73(25,8%) serous cystadenoma, 45 (15,9%) dermoid cysts, 22 (7,8%) paraovarian cysts, 2 (0,7%) adenocarcinoma were detected after histological examination. In patients with RMI >200, 25% of benign ovarian tumors, 34,6% of borderline and 40,4% of malignant tumors were verified. Conclusions: RMI when used in the presence of a pelvic mass is a useful triage tool to determine those women who should be referred to a gynaecological oncologist. During laparoscopy, in cases of intraoperative malignancy suspicion staging should be performed: videorecord of the surgery, biopsy of the adnexal mass and contralateral ovary, biopsy of the omentum and peritoneum, and aspiration of the peritoneal fluid for cytological examination.