Introduction: Breast cancer is on rise in Asian population. Identification of more prognostic and predictive factor in breast invasive carcinoma is need of the time in order to provide best possible management to improve the outcome. Aim: the aim of the study is to observe Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) association with various clinicopathological parameters and molecular groups based on immunohistochemistry in invasive ductal breast carcinoma. Methodology: Eighty-three patients undergoing modified radical mastectomy with primary microscopically proven invasive ductal carcinoma were recruited from two tertiary care hospitals, Pakistan. Grossing __ampersandsignamp; reporting including Biomarker was performed as per College of American Pathologists (CAP) protocol. Molecular groups were formed. Data was entered and analyzed using IBM SPSS version 27. Results: CEACAM5 was overexpressed in 78% of patients and negative in 22% of patient (p__ampersandsignlt;0.001) of invasive ductal carcinoma breast (Figure 1). The mean age __ampersandsignplusmn; SD of CEACAM5 positive patient was 49.94 __ampersandsignplusmn; 11.4 years. Statistically significant association was observed with age, tumour stage, glandular formation, mitosis, Nottingham histological grade and non-triple negative molecular group. Conclusion: The increasing incidence of breast carcinoma in Pakistani population warrants dire need of new and cheap modalities for therapeutic assessments in order to provide a suitable treatment plan to patients. Significant association has been observed with various clinicopathological parameters and molecular group. CEACAM5 can be considered, as a predictive factor and follow-up marker, however, large-scale validation follow-up studies are required.