Objective To study the influence of different body serum iron levels on follicle stimulating hormone (FSH),luteinizing hormone (LH) and uterine ovarian index,and explore the body serum iron level effects on female mice sexual maturity further.Methods 36 three weeks C57BL/6J female mice were randomly divided into the normal control group,strengthen-iron 1 group and strengthen-iron 2 group,12 cases in each group.The normal control group with normal diet(310mgFe/kg),strengthen-iron 1 group and strengthen-iron 2 group were given high -iron diets(respectively with 465mgFe/kg and 620mgFe/kg) after born 3 weeks.each group body,uterus and ovary mass after 2 weeks were checked;colorimetric method was used to detect the serum iron level;the serum follicle stimulating hormone (FSH) and luteinizing hormone(LH) were detected by chemiluminescent immunoassay.Results The body of mice serum iron levels,uterine ovarian index (uterine ovarian wet mass/body mass) and follicle stimulating hormone(FSH) level of strengthen-iron 1 group and strengthen-iron 2 group were higher than those of normal control group (F =9.11,11.11,7.09,all P ＜ 0.01).Luteinizing hormone (LH) level of the strengthen-iron group was higher than those of normal control group (F =3.89,P ＜ 0.05).Conclusion Uterine ovarian index,follicle stimulating hormone level and luteinizing hormone level were affected with increased serum iron level;It suggests that the increasing serum iron level can cause female mice sexual maturity in advance.