Background: Endometrial receptivity is defined as a temporary unique sequence of factors that make the endometrium receptive to the embryonic implantation. Histological evaluation, now considered to add little clinically significant information, should be replaced by functional assessment of endometrial receptivity. A large number of functional molecular mediators have been identified to date, including adhesion molecules. Thus, endometrial biopsy samples can be used to identify molecules associated with uterine receptivity to obtain a better insight into human embryo implantation. Objectives: To investigate E-cadherin expression in the endometrium throughout the menstrual cycle of fertile females. Patients, Materials and Methods: Under simple analgesia, fractional endometrial biopsies from anterior, posterior, fundal walls, and the cervix of (32) fertile females (age= 29.91± 5.9 year, parity= 3.6±2.1) were taken at different days of the menstrual cycle. The immunohistochemical (IHC) stained tissues were analyzed using computerized image analysis for measurement of PI of E-cadherin which is ratio of the number of stained cells to the number of total cells. PI were measured in three regions: stromal, membranous, and glandular epithelium. Results: E-cadherin expression in the endometrium is up-regulated in the proliferative phase and down-regulated in the secretory phase of the menstrual cycle. The PI of E-cadherin in the glandular epithelium of the anterior wall of the endometrium was significantly lower than that of posterior and fundal walls (P=0.027). The PI of E-cadherin in the endocervical epithelium was significantly higher than that in the anterior, posterior, and fundal walls of the endometrial cavity (P=0.004). Conclusion: E-cadherin might have a role in embryo implantation.