Background: Endometrial integrin expression changes might be a reason for implantation failure in polycystic ovarian syndromes (PCOS).Objective: Assessment of integrin genes and proteins expression upon endometrium in the PCOS experimental mouse model was the main goal of this study.Materials and Methods: 30 NMRI female mice were equally divided into control, experimental (PCOS; received estradiol valerate (40 mg/kg)) and sham group (received; olive oil). After 8 weeks, each group was hyper stimulated by 7 IU PMSG and then, after 48hrs, 7 IU HCG was injected. Vaginal plaque was checked. After 5 days, Progesterone and estradiol levels and endometrial tissues were investigated to evaluate of α4, αv, β1 and β3 integrins gene and protein by qPCR method and immunohistochemistry, respectively.Results: Tissue samples were assessed and showed that level of progesterone was significantly decreased in PCOS group. Results of molecular part in the amount of αv, β3, β1 and α4 gene expressions showed a great difference in β3 and αv genes expressions between experimental groups. αv, β3, α4 and β1 proteins in the endometrial stroma in the control group were expressed, but they were not detected in PCOS group.Conclusion: According to the results, integrins had different expression patterns in different areas of the endometrium; such as epithelial and stromal. It seems that in PCOS, this pattern has changed and the results might have a great influence on implantation failure. Therefore, this study suggests that a great attention to this problem may be essential in patients who are involved.