Implantation is a complicated developmental process. Some hormones and cytokines are involved in the regulation of the implantation by regulating functions of the endometrium and the embryo. Oligosaccharide antigen Lewis Y is specifically expressed on embryo surface and plays an important role in implantation. In this study, effects of Lewis Y on secretion and gene expression of EGF and EGF receptor of the embryo were investigated. Embryos were pre-incubated with Le(Y) specific antibody AH6 for 3 h, then antibody was removed, immuno-dot blots and RT-PCR were used to analyze the secretion of EGF and EGF receptor and their gene expression in the embryo at different times after pre-incubation. The results showed that, when blocked by AH6 antibody for 1.5 h, the secretion and expression of EGF in the embryo were significantly declined, and the alteration was continued to over 6 h; and those of EGF-R were slightly decreased after blocking. The results suggest that Lewis Y oligosaccharide on the surface of embryo may be involved in the regulation of embryo development and implantation, by affecting the expression and secretion of EGF in embryo.