Angiogenesis is an important process in endometrial development and embryo implantation, vascular endothelial growth factor (VEGF) regulates this process via interaction with its receptors ; Flt-1 and KDR. This work was carried out to study the immunoexpression of VEGF receptors in the endometrium at different ages and reproductive phases and to correlate them with the histological pictures in these phases. Seventy female albino rats were included in this study. They were divided into three groups represent the prepubertal period, the reproductive period and the postmenopausal period, vaginal smears were done to determine the estrous cycle phases, the uteri removed from sacrificed rats and processed for staining with H and E and immunohistochemical staining for Flt-1 and KDR. The expression of VEGF receptors revealed to be highest in the pubertal age group with marked expression of these receptors in the proestrus phase followed by estrus phase and this supports the role of sex hormones especially estrogen hormone in regulating VEGF receptors expression. Flt-1 receptor has the predominance in the expression in endometrial epithelial, stromal and blastocyst cells while KDR receptor has the superiority in the endometrial endothelial cells. In conclusion, the up-regulation of Flt-1 and KDR could be involved in regulating the endometrial endothelial cell proliferation and increasing the endometrial vascular permeability especially at the implantation sites.