Objective To observe the effects of chronic arsenic exposure on mRNA expression of estrogen receptor-binding fragment-associated gene 9 (Ebag9) and estrogen-responsive finger protein (efp) in uterus and ovary of female rats.Methods Fifty female Wistar rats were randomly divided into five groups according to arsenic (As2O3) concentrations given through drinking-water:0.00 (control),0.05,0.10,0.20,0.40 mg/L arsenic exposure groups and real-time RCR (RT-PCR) was used to detect the mRNA expression of Ebag9 and efp in uterus and ovary tissue at the 31 weeks of experiment.Results The mRNA expression levels of Ebag9 and efp of the 0.00,0.05,0.10,0.20,0.40 mg/L arsenic exposure groups were respectively as follows:0.761 ± 0.178,0.521 ± 0.130,0.544 ± 0.035,0.525 ± 0.198,0.498 ± 0.240 and 0.795 ± 0.171,0.874 ± 0.077,0.797 ± 0.066,0.796 ± 0.040,0.832 ± 0.096.Compared with control group,a decreased tendency was observed in Ebag9 mRNA level(with P value 0.055 in 0.40 mg/L arsenic exposure group) and increased tendency in efp mRNA level in experimental groups (all P ＞ 0.05).The mRNA expression levels of Ebag9 and efp in ovary of the five groups were by turns:0.702 ± 0.484,0.719 ± 0.336,0.693 ± 0.095,0.706 ± 0.055,0.728 ± 0.073 and 0.924 ± 0.061,1.009 ± 0.034,0.930 ± 0.085,0.929 ± 0.068,1.012 ± 0.101.Compared with control group,the expression level of Ebag9 mRNA showed a increased tendency in 0.05,0.20,0.40 mg/L arsenic exposure groups(all P ＞ 0.05).The efp mRNA level increased in experimental groups,with significant difference in 0.05,0.40 mg/L groups (all P ＜ 0.05).Conclusions The expression of efp mRNA has changed in ovary of female rats exposed to chronic arsenic.Arsenic may act as an environmental endocrine disruptor to exert its effect.