Abstract: Objective:To investigate the clinical characteristics,diagnosis,therapy and prognosis of primary ovarian sarcoma.Methods: Retrospectively the information of two cases of primary ovarian sarcoma in our hospital and pertinent literatures were analyzed and reviewed.Results: The two cases of primary ovarian sarcoma developed rapidly,could not be diagnosed at early stage,was hard to surgery and had worse prognosis.Conclusion: To diagnose earlily primary ovarian sarcoma is very difficult.Its diagnosis depends mainly on pathology.The image of caryocinesis of this disease mostly can be seen and the pathologic image of caryocinesis can also be observed.Immunohistochemistry result displays vimentin（+）.The degree of malignancy of this disease is very high.Its therapeutic efficacy and prognosis are both worse.chemotherapy and radiotherapy can be helpful to be combined with surgery.