Objective To investigate the clinical pathologic features of ovarian malignant mesoderm mixed tumor (malignant mixed mesodermal tumor of uterus ,MMMT ) ,and its differential diagnosis ,clinical treatment and prognosis .Methods A retrospec‐tive analysis of the clinicopathological data of 9 patients with MMMT in our hospital from January 1985 to December 1985 was per‐formed ,and the clinicopathological data included routine paraffin section of HE staining and special staining and immunohistochemi‐cal study .Results Results showed that 8 cases were examined by ultrasound with side ovarian tumor ,1 case of patients with bilat‐eral ovarian tumors .Histological examination showed that there was 5 cases of endometrial carcinoma in epithelial components ,3 ca‐ses in clear cell carcinoma ,1 case in mucous adenocarcinoma .Composition of mesenchymal cells were fusiform or irregular shape , weaving or beam pattern ,or chaotic ,which 4 cases showed chondrosarcoma ,2 cases showed bone sarcoma component and glandular epithelial cell keratin and stromal elements vimentin (Cytokeratin ,CK) of 9 cases were + ,and estrogen receptor (estrogen recep‐tor ,ER) detection of 3 cases were + ,Progesterone receptor(PR) detection of 2 cases were + ,protein (desmin) of 2 cases were + ;highly glycosylation type I transmembrane glycoprotein (CD34) of 1 case was + .Conclusion Histological appearance is the main detection methods of ovarian malignant germ layer in the diagnosis of mixed tumor ,and B ultrasonic and CA125 inspection at the same time can effciently improve the accuracy of clinical diagnosis .