Abstract:In order to explore the effect of quinestrol and progestin (EP-1) on reproductive system, appropriate concentration and reproduction recover duration of male Yangtze voles, Microtus fortis, the experimental voles were treated using gastric perfusion with EP-1 and some of them were dissected at different time. The results showed that EP-1 affected the anti-fertility of male Yangtze vole and the effect could recover. Compared to the control group, testicular coefficient and epididymis coefficient were decreased significantly (P＜0.01), testicle atrophied and be damaged, sperm density and testosterone contents decreased, lower rate of reproduction as well. The effective fertility control time of group were about 40, 55 and 60 d for 10, 30, 60 mg/kg respectively. The recover order of reproductive tissue was testicle, epididymis, and sperm.