Competent endometrial receptivity is a prerequisite for successful embryo implantation. Identification of novel key molecules involved in endometrial receptivity is essential to better interpret human implantation and improve pregnancy rates in assisted reproduction treatment. The isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics was performed to profile the proteomes of the prereceptive( LH+2, n=4) and receptive (LH+7, n=4) endometrial tissues. One hundred seventy-three differentially expressed proteins (DEPs) between LH+2 and LH+7 endometrial samples were identified. Integrated analysis of the proteomic data and published transcriptomic data was performed to identify the concordant DEPs with differential expression at both mRNA and protein levels. The protein-protein-interaction (PPI) network analysis were performed on concordant DEPs.We first identified 63 novel concordant DEPs and 5 hub proteins (ACSL4, ACSL5, COL1A1, PTGS1 and PLA2G4F) between LH+2 and LH+7 endometrial samples. ACSL4 was predominantly expressed in endometrial epithelial cells and its expression was significantly upregulated in the LH+7 endometrium and significantly downregulated in repeated implantation failure (RIF) patients. Knockdown of ACSL4 in endometrial epithelial cells induced the down-regulation of endometrial receptivity markers (HOXA10, COX2 and LIF) and the significant decrease of implantation rate during in vitro implantation analysis. This study provides the first gel-independent quantitative proteomes of the LH+2 and LH+7 human endometrium using iTRAQ technology. The identified concordant DEPs and hub proteins open a new avenue for future studies aimed at elucidating the underlying mechanisms governing endometrial receptivity. ACSL4 was identified as a novel regulatory molecule in the establishment of endometrial receptivity and might play important roles during implantation.