Background: The purpose of this work is to study the immunohistochemical expression of β-catenin in serous ovarian carcinoma and to investigate its relationship with clinicopathological features Methods: A retrospective study at the Egyptian National Cancer Institute - Cairo University examined 67 ovarian serous carcinoma cases from 2015-2017, assessing β-catenin expression using automated immunostaining. Results: The age of patients ranged from 26 to 76 years. β-catenin expression was localized in the cytoplasm, membrane or both. It was considered aberrant (positive) in presence of cytoplasmic staining with/without membranous staining in ≥ 10% of tumor cells. Thirty cases showed cytoplasmic staining, eighteen cases showed preserved expression in cell membrane, fifteen cases showed combined cytoplasmic and membranous, while 4 cases were completely negative. A significant correlations were observed between β-catenin positivity and tumor grade and p53, (p value = 0.004 in both). Conclusions: β-catenin positivity correlated significantly with tumor grade in ovarian serous carcinoma, with most of low grade serous carcinoma cases exhibit membranous β-catenin reaction, whereas most of high grade serous carcinoma cases exhibit cytoplasmic reaction. Finding a new target for Wnt signaling pathway can contribute to effective targeted therapy.