Objective: To evaluate the frequency and pattern of E-cadherin immunoexpression in epithelial ovarian tumors (EOTs) and its association with histological subtypes and tumor grade. Material and Methods: This descriptive cross-sectional study was conducted in the Department of Pathology at Pakistan Institute of Medical Sciences. A total of 89 histologically confirmed cases of epithelial ovarian carcinoma were included. Immunohistochemistry for E-cadherin was performed, and both staining intensity and the proportion of positively stained tumor cells were assessed. Correlation with tumor subtype and grade was analyzed. Results: Serous carcinoma was the most common subtype (77.52%), followed by mucinous (13.48%), endometrioid (4.4%), and clear cell carcinoma (4.4%). E-cadherin expression was positive in 56 cases (62.92%) and negative in 33 cases (37.07%). Among serous carcinomas, 66.66% showed positive staining, while 33.3% were negative. Mucinous carcinomas demonstrated E-cadherin positivity in 58.33% of cases. Notably, endometrioid carcinomas showed the highest frequency of E-cadherin loss, with 75% of cases staining negative. Additionally, 50% of clear cell carcinomas lacked E-cadherin expression. A trend of decreasing E-cadherin expression with increasing tumor grade was observed. Conclusion: Loss of E-cadherin immunoexpression was observed in 37% of epithelial ovarian tumors, with the highest reduction noted in high-grade and endometrioid subtypes. These findings suggest that E-cadherin may serve as a potential prognostic marker in assessing tumor aggressiveness and differentiation in epithelial ovarian carcinomas. Keywords: Epithelial ovarian cancer, Epithelial ovarian cancer, Endometrioid carcinoma, Mucinous carcinoma.