Objective: identification and description of clinical and morphological characteristics of rare forms of stromal cell tumors of the ovaries.Materials and methods. Retrospectively processed over 10 thousand case histories of patients with various ovarian tumors who were examined and treated at the N.N. Blokhin National Medical Research Center of Oncology, Ministry of Health of Russia and the National Center for Oncology and Hematology of the Ministry of Health of Kyrgyz Republic. In 473 patients were diagnosed stromal cell tumors, among them 3 cases of rare forms of tumors of the stroma of the sex cord were identified: stromal tumor from Sertoli cells, malignant luteoma of the ovary, lipid‑cell tumor from Leydig cells. All patients underwent a planned morphological study of surgical material and immune-histochemical study.Results. The detailed data of clinical observations of rare types of tumors, which was presented in the literature by isolated cases, are presented, the description of which in the literature is presented by isolated cases. The possible effect of clinical and morphological characteristics on the survival of patients with rare forms of stromal cell tumors of the ovaries were analyzed.Conclusions. The necrobiotic changes in the tumor, the degree of malignancy, and the stage of the disease are potential predictors of poor prognosis in patients with rare forms stromal cell tumors of the ovaries which require confirmation in a larger sample of patients.