The role of trefoil factor 3 (intestinal) (TFF3) has been analyzed in numerous cancers, such as breast and gastrointestinal cancer, and has been associated with poor prognosis. However, the role of TFF3 in ovarian cancers is not clear. Expression analysis of TFF3 in 91 ovarian cancer patients was performed by immunohistochemistry of primary paraffin-embedded tumor samples. The results were scored according to staining intensity and percentage of positive tumor cells resulting in an immune-reactive score (IRS) of 0-12. These results were correlated with clinicopathological characteristics and survival. TFF3 expression in our patient cohort exhibited a tendency towards improved overall and progression-free survival (PFS). In TFF3-positive serous and high-grade serous ovarian cancers, the median PFS was 27.6 months [95% confidence interval (CI): 0-55.7] vs. 15.2 months in TFF3-negative tumors (95% CI: 13.8-16.6) (P=0.183). The median overall survival was 53.9 months in TFF3-positive tumors (95% CI: Non-applicable) vs. 44.4 months in TFF3-negative cases (95% CI: 30.5-58.3) (P=0.36). TFF3 negativity was significantly associated with higher tumor grade (P=0.05). Based on our results, further studies are required in order to elucidate whether survival and chemosensitivity are affected by TFF3 expression in ovarian cancer.