Objective: To investigate the effects of estrogen and progesterone on the expression of vascular endothelial growth factor (VEGF) and its receptors (VEGFR) in mouse uterus. Methods: 3-week-old immature female mice were randomly divided into 7 groups and treated with corn oil, estradiol (E2) of 1.5, 3.0, 10, 25 ng, progesterone (P) of 100 ?g and (E_2 10 ng + P 100 ?g)/mouse, respectively. After the treatment for 48 h, mouse uterus was collected to isolate total RNA. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of mRNA isoforms of VEGF and its receptors in mouse uterus. Results: Compared with control, both E_2 and P significantly increased the expression of VEGF164 and VEGF120 mRNA in mouse uterus. The expression of VEGFR2 mRNA, not VEGF1 mRNA, was decreased by E_2 treatment in a dose-independent manner. Conclusion: Both estradiol and progesterone up-regulated the expression of VEGF, but estradiol down-regulated the expression of VEGFR2 in mouse uterus.