Abstract:Effect of levonorgestrel-quinestrol (EP-1) on fertility of female Mongolia gerbils, Meriones unguiculats, was researched. The samples were divided into 3 groups, including the multi-dose treatment groups (at the dose of 10mg/kg for 3d each week and for consecutive 4 weeks), single-dose treatment group (at the dose of 10mg/kg) and CK. After 4 weeks, the ovary and uterus organ coefficient, ovary section, the reproductive hormones (LH and E2) content in the blood serum and the reproduction rate were tested in the laboratory. There are significant differences between the multi-dose treatment groups and the control group; the fertility of the treatment group was completely prohibited, and the reproductive organ as well as the hormone level were significantly reduced. No significant differences of the reproductive organ and the hormone level between single-dose treatment group and the control group, and the fertility of Mongolia gerbils was normal compared with the control group when tested after one month. The results indicated that females of Mongolia gerbils treated with multiple dose of EP-1 are very potential for fertility control of Mongolia gerbils.