Aim: To assess the diagnostic value of the risk of malignancy indices and simple ultrasound-based rules in preoperative differentiation of adnexal masses. Material and methods: Retrospective examination of 87 patients admitted to hospital due to adnexal tumors. The lesions were evaluated on the basis of international ultrasound classification of ovarian tumors and four risk of malignancy indices were calculated based on ultrasound examination, concentration of CA 125 and menopausal status. Results: The patients were aged between 17 and 79, the mean age was 44.5 (standard deviation SD=16.6). Most of the patients (60.91%) were before their menopause. The sensitivity of the simple ultrasound-based rules in the diagnosis of malignancies equaled 64.71% and the specificity constituted 90.00%. A significant statistical difference in the presence of the malignant process was demonstrated in relation to age, menopausal status, CA 125 concentration and analyzed ultrasound score. All indices were characterized by similar sensitivity and specificity. The highest specificity and predictive value of malignant lesions out of the assessed ones was demonstrated by the risk of malignancy index proposed by Yamamoto. The risk of malignancy index according to Jacobs, however, showed the highest predictive value in the case of non-malignant lesions. Conclusions: The multiparametric ultrasound examination may facilitate the selection of patients with adnexal tumors to provide them with an appropriate treatment – observation, laparotomy and laparoscopy. These parameters constitute a simple ambulatory method of determining the character of adnexal masses before recommending appropriate treatment.