Fascin1 (FSCN1) involved in cell motility and filopodia assembly plays important roles in biological processes such as cancer invasion and metastasis of multiple epithelial tumors. High-grade serous ovarian carcinoma (HGSOC) is aggressive and metastatic by acquiring an invasive phenotype and this step requires remodeling of the actin cytoskeleton. Thus, the present study aimed to investigate the expression of fascin1 in HGSOC tissues as well as its clinical significance such as prognostic predictors and its utility of therapeutic target. Fascin1 and β-catenin were evaluated using immunohistochemistry on a tissue microarray of 79 HGSOC. Small interfering RNA (siRNA) approach was used to knock down fascin1 expression in ovarian cancer cell lines to determine whether fascin1 contributes to tumor cell proliferation, migration and invasion. Fascin1 expression levels were determined by western blot analysis after siRNA transfection using two human ovarian cancer cell lines (SKOV3 and OVCAR3). Fascin1 overexpression was significantly correlated with lymph node involvement, distance metastasis and high International Federation of Gynecology and Obstetrics (FIGO) stage (III/IV) (P<0.05). A Kaplan-Meier analysis showed that the fascin1 expression group was significantly associated with poor overall survival (P=0.010). We showed that inactivation of fascin1 by siRNA transfection led to a drop in cell viability, and significantly decreased tumor cell proliferation, migration and invasiveness compared to untransfected cells. We found that fascin1 expression is a potential poor marker of prognosis for patients with HGSOC and knockdown of fascin1 suppresses ovarian cancer cell proliferation and migration, this could be applied for therapeutic targets in ovarian cancer treatment.