Polyamines are key regulators in cell growth and differentiation. It has been shown that ornithine decarboxylase was essential for post-implantation embryo development and over-expression of spermidine/spermine N1-acetyltransferase (Sat) will lead to ovarian hypofunction and hypoplastic uteri. However, the expression and function of polyamine-related genes in mouse uterus during early pregnancy are still unknown. In this study, we investigated the expression, regulation and function of polyamine-related genes in mouse uterus during peri-implantation period. Ornithine decarboxylase expression was strongly detected at implantation sites and stimulated by estrogen treatment. The expression of ornithine decarboxylase antizyme 1 and Sat was also highly shown at implantation sites and regulated by ornithine decarboxylase or polyamine level in uterine cells. Embryo implantation was significantly inhibited by -difluoromethylornithine (DFMO), an ornithine decarboxylase inhibitor. Moreover, the reduction of ornithine decarboxylase activity caused by DFMO treatment was compensated by the up-regulation of S-adenosylmethionine decarboxylase gene expression. Collectively, our results indicated that the coordinated expression of uterine polyamine-related genes may be important for embryo implantation.