Granite is widely distributed around Tangshuizhai geothermal area. As the rock is integrity and poor in penetration in the depth, the geothermal field is classified as zoned reservoir. The data of Tritium concentra- tions in precipitation and in Tangshuizhai hot springs indicates that the spring water are of meteoric origin and the circulation time is at least ten years. As small volume, limited water storage and less geothermal reserves, the exploitation of the geothermal field should be in small scale. The hot springs can only be used for health drinking or bathing.