The aim of this study is to determine the correlation of histopathological subtype with frozen section examination and the importance of immunohistochemical analysis ofovarian malignancies which also include metastatic ones. This study is a retrospective study that have included 55 patients who have been operated for adnexial tumor andhave the diagnosis of malignancy during surgery by frozen section or after surgery by final pathologic examination done by immunohistochemistry (IHC). The mean ageof the patients with malignant ovarian tumor is 52.33 ± 15.5 years. When the pathologic diagnosis reports examined it has been found that 34 of 55 patients (61.8 %) havehad epithelial type, 9 have had sex cord stromal tumor, 3 have had germ cell type and 9 of the patients have had metastatic ovarian cancer. Survival rates have been foundas 70.6 % for epithelial ovarian cancer, 100 % for sex cord stromal tumors, 100 % for germ cell tumor and 44.4 % for metastatic tumors. Despite the rapid development inexamination and imaging methods, histopathology is the pivotal issue in the diagnosis and also in sub-type diagnosis of pelvic mass lesions. The improvement is better inpatients evaluated and operated in gynecologic oncology centers. The two important factor in this subject is the experience of the surgeon for maximum salvage from thetumoral burden and the well examination by frozen section the immunohistochemical methods for the discrimination of gastrointestinal tumors which can mimic ovarianprimary tumors. Immunohistochemical methods have very important progression in diagnosis of cancer, its origin and subtypes and however IHC also could have a keyrole in treatment of cancer by targeted therapy.