Epithelial ovarian cancer (EOC) prognosis is associated with International Federation of Gynecology and Obstetrics (FIGO) staging, cancer cell classification, patient age, and residual tumor size. However, the molecular markers for predicting EOC prognosis remain to be explored. In this study, we investigated the expression of CD24, COX-2, and p53 in EOC, and their relationships to clinical prognosis. We found that the expression of CD24 was detected in the cell membrane in 90.6 percent (58/64) of EOC cases and in the cytoplasm in 54.7 percent (35/64) of EOC cases; 78.6 percent (11/14) cases of borderline tumors had CD24-positive staining in the cell membrane. All 9 cases of benign tumors were negative for CD24 staining. Expression of CD24 correlated with the nuclear expression of p53, but not with the expression of COX-2. Overexpression of CD24 is an independent factor associated with tumor metastasis, a low survival rate, and a short survival time. Our results suggest that CD24 may be a valuable molecular marker for predicting prognoses of patients with EOC.