Background: Embryo implantation is a key step in establishing pregnancy and a major limiting factor in IVF. The inner lining of the uterus, the endometrium, must transform from non-receptive to receptive to allow embryos to implant but the mechanisms governing endometrial receptivity are not well understood. Our laboratory recently discovered that glycoprotein podocalyxin (PODXL) is an important negative regulator of human endometrial receptivity. PODXL is highly expressed on the apical surface of all epithelial and endothelial cells in the non-receptive endometrium, but down-regulated specifically in the luminal epithelium at receptivity. Furthermore, PODXL inhibits embryo attachment and invasion, demonstrating that down-regulation of PODXL is essential for implantation. Our previous study indicated that this down-regulation is mediated by progesterone, however, the detailed molecular regulations are unknown. Aim: To investigate the role of microRNAs (miRNAs) in regulating PODXL for receptivity. Methods: Primary human endometrial epithelial cells were isolated from women, cultured in the presence of estrogen (E, mimics the non-receptive state) or estrogen plus progesterone (EP, mimics the receptive state), and screened against 13 bioinformatically predicted miRNAs that may target PODXL. The miRNAs found to be significantly regulated by hormonal treatment were subsequently validated by real time RT-PCR, and their functional importance was determined in in vitro embryo implantation models. Results: Two miRNAs were found to be significantly up-regulated in EP compared to E treated cells. To confirm the functional importance, these miRNAs were transfected into endometrial cell line Ishikawa cells in the absence of progesterone, and both significantly down-regulated PODXL at both the mRNA and protein levels. Moreover, both miRNAs significantly enhanced embryo implantation in in vitro models. Conclusions: This study identified specific miRNAs that are up-regulated by progesterone which target PODXL to promote endometrial receptivity; these results may potentially lead to therapeutics to improve IVF success in those with endometrial-related infertility.