According to the meteorological data from 1955 to 2007 in northern and southern Qinling Mountains, the impact of El Nino on the precipitation is analyzed. The precipitation difference between northern and southern Qinling Mountains in response to the El Nino phenomenon is also compared, as well as its hazard effect.The result shows that the precipitation changes in response to El Nino between both sides are similar in trends but different in range. In the El Nino year,the precipitation of northern mountain decreases greater than that of southern,while the precipitation in Southern increases larger than that in Northern in the following year. The Qinling Moutains has an obvious role as the boundary of northern and southern. The precipitation margin in the southern and northern Qinling Moutains is becoming larger under the global change, with El Nino phenomenon making this gap wider.

El Nino; precipitation change; hazard effect; the southern and northern Qinling Moutains