To evaluate the effect of serum progesterone and estradiol concentrations on day of injecting human chorionic gonadotropinon(HCG) on the pregnancy outcomes in the invitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) patients. From Sep. 2011 to Sep.2012，1 270 fresh IVF cycles who comply with relevant conditions were analyzed retrospectively in Reproductive Medicine Center in Renmin Hospital of Wuhan University. And according to the serum progesterone value，the patients are divided into two groups，One group is the value of serum progestrone which is less than 2.0 pg/mL on the day of injecting HCG，the other is the value of serum progestrone which is equal or greater than 2.0 pg/mL on the day of injecting HCG.Then in terms of the ratio about progesterone and estradiol (P/E2)，the patients are divided into two groups with 0.6 as P/E2 cut-off point. Compared women’s age，duration of infertility，basic follicle stimulating hormone (FSH) values，the total doses of gonadotropin，the duration of stimulation，number of oocytes retrieved，number of MII oocytes，number of fertilization，number of cleavage，number of high qualified embryo，number of embryos transferred per cycle，estradiol level on the HCG day，clinical pregnancy rate (%)，embryo implantation rate (%). The higher concentration of progesterone group had more total doses of gonadotropin，duration of stimulation，number of oocytes retrieved，number of MII oocytes，number of cleavage，E2 value，but the clinical pregnancy rate, embryo implantation rate were statistically decrease.There was an increase in the age of female patien, basic FSH values and total doses of gonadotropin, duration of stimulation,number of oocytes retrieved, number of fertilization,number of high qualified embryo，P values in higher P/E2 ratio group. However, there was no obvious difference was found between the pregnancy outcome. Conclusion on day of injecting HCG，serum progesterone levels can reduce clinical pregnancy rates and embryo implantation rate.