Mammalian endometrial glands are essential for the embryo development by synthesizing and secreting nutrients.Evidences for the existence of endometrial epithelial stem cells have been reported recently, but little is known about the epithelial stem cell marker.This study aimed to screen and identify potential bio-marker of endometrial epithelial stem cell.By single cell Q-PCR with 96 pairs of primers including embryonic stem cell markers, somatic stem cell markers and transcription factors involved in the development of uterus, we detected gene expression of 96 single cells from postnatal-day-7 mice endometrial epithelia, after clustering and principal component analysis of the expression data, we identified a subgroup of cells that uniquely expressed high level of aldehyde dehydrogenase (ALDH) 1 gene, and the expression pattern of aldhl gene was highly correlated with the expression of stem cell marker, transcript factors as well as wnt signaling related genes of pax2, lgr5, emx2, cd133, sox9, msil, ki67, ezh2, wnt7a, tert, ctnnb, lgr4.FACS analysis showed that there was a small population of CD326 positive and ALDH high cells in the uterus epithelia by using ALDEFLOUR kit, after FACS isolating the CD326 positive and ALDH high cells from postnatal-day-7 mice as well as adult mice, we found that these cells also expressed high level of stem cell, transcript factors as well as wnt signaling related genes of cd133, emx2, ezh2, ki67, lgr5, msil, pax2, wntTa, which was consistent with the single cell QPCR results.Immunofluorescence analysis showed that ALDH1 expressed highly in newly formed gland epithelia as well as invaginating luminal epithelia during the formation of endometrial gland in postnatal-day-7 mice, which co-expressed cell proliferation marker Ki67 and stem cell marker SSEA1,while the expression of ALDH1 was in the endometrial gland epitheha of the basal layer of the endometrium from the sexual mature mice.These results indicated that ALDH1 positive epithelia may the candidate stem cell of endometrial epithelia that involved in the postnatal gland formation and regeneration of the luminal epithelia from the basal gland epithelia during the menstrus cycle.