Abstract: Objective To study the expression of CD44V6 in ovarian carcinoma and to investigate its clinical significance in malignant ovarian tumor. Methods The immunohistochemical stain method was used to detect the expression proteins of CD44V6 in tissue samples of 41 malignant ovarian tumors,20 benign ovarian tumors and 21 normal controls. Results (1)The positive expression rates of CD44V6 protein in malignance were significantly higher than that in benign and control;(2)The expression levels of CD44V6 in residual tumor(diameter>2cm)were significantly higher than that in residual tumor (diameter≤2cm). (3)The positive expression rates of CD44V6 in metastatic focus were significantly higher than that in primary focus;the positive expression rates in the pirmary focus with metastasis were significantly higher than that without metastasis. (4) The short term curative effects of patient with positive expression of CD44V6 were significantly lower than that of negative patients with such expression.(5) No significant correlation was observed between the positive expression rate of CD44 and pathological type,or histological grade in cancer tissue. Conclusion (1)CD44V6 was correlated with the carcinogenesis and progress of tumor.(2)The over expression of CD44V6 was correlated with the metastasis of malignant ovarian tumor,it may be used for predicting the metastasis of cancer.(3) The over expression of CD44V6 was correlated with the curative effects,it would be a new marker for evaluating the curative effects and prognosis.