Abstract: Objective To investigate the expression of receptor tyrosine kinase EphB6 in ovarian serous carcinoma and its relationship with clinicopathological characteristics. MethodsImmunohistochemical staining was subjected to a set of paraffin fixed tissue samples including 55 cases of ovarian serous carcinoma， 24 cases of benign carcinoma， 37 cases of borderline carcinoma and 20 cases of normal fallopian tube. The relationship between the expression of EphB6 in ovarian serous carcinoma and clinicopathological parameters and survival was analyzed. ResultsHigh expression of EphB6 was detected in 100.0％（20／20） of normal fallopian tube samples， 100.0％（24／24） of benign carcinoma， 78.4％（29／37） of borderline tumor and 18.2％（10／55） of ovarian serous carcinoma（P＜0.001）. The expression of EphB6 was significantly associated with differentiation， TNM stage and Ki-67（P＜0.005）. The median overall survival of high-level expression group was 103 months， higher than 69（95％CI：26-105）months of moderate and low-level expression group with significant difference（P=0.046）. Conclusion It shows that EphB6 is a new biomarker for distinguishing high and low-grade ovarian serous carcinoma， and maybe a potential prognostic marker.