Abstract: This paper outlines hydrogeologic condition and hydro-geochemical feature in the Southern part of North-South Earthquake Belt in China and maps abnormal map of microelements of B,F,Li and Sr. At the same time,the relationship between hydro-geochemical feature and earthquake is analyzed. The research results indicates:(1) Earthquake,geothermal heat and microelement abnormal areas are controlled by tectonic.Their distributions in space are obviously same.(2) High-middle temperature water areas,especially the areas of high-middle heat spring,are always the strong regions of earthquake activity.But the strong earthquake area does not always occur in high-middle heat spring.(3) During the process of earthquake formation water temperature,flow quantity and hydro-geochemical component in geothermal wells and hot springs may be changed. The change of hydro-chemical components,especially microelement in hot springs may be one of information to forecast earthquake.