Objective: To observe the expression of p-STAT3, Twist, and E-cadherin in ovarian epithelial carcinoma and normal ovarian tissue and to investigate the correlation and significance among them and clinicopathological parameters of ovarian cancer. Materials and Methods: The expression of p-STAT3, Twist, and E-cadherin in 60 cases of ovarian cancer were detected by immunohistochemistry. Forty normal ovaries were used as controls. Results: The positive rates of p-STAT3, Twist, and E-cadherin in ovarian cancer were 68.3%, 65%, 28.3%, and those of normal ovarian tissue rates were 20%, 27.5%, and 87.5%. The differences were statistically significant and the expressions of p-STAT3 and Twist were positively correlated, but negatively correlated with E-cadherin expression. The expressions of P-STAT3, Twist, and E-cadherin were correlated with the ovarian cancer clinical stage, tumor differentiation, and lymph node metastasis (p < 0.05). Conclusion: In ovarian epithelial carcinoma, the expressions of p-STAT3 and Twist are related to the biological characteristics of tumor to a certain extent, and both of them may be involved in epithelial and mesenchymal transition of epithelial ovarian cancer.