By means of electrical sounding and inversion interpretation with RGIS, the authors investigated the relationship between Xiatang warm spring and Checun-Lushan fault and found out the hydrogeological conditions within 1 500 m on both east and west sides of Xiatang warm spring. The results reveal that Xiatang warm spring is controlled by the EW-trending Checun-Lushan fault (F1), and also affected by the NE-trending F4 fault.. The former fault is the heat-conducting structure of level 1, and is also the major passage for upward convection of the deep heat source; the latter fault is the heat-conducting structure of level 2. Driven by the topography and the difference of hydraulic head pressure, the underground water migrates slowly along the fault zone from the west to the east. During the movement, the underground water is affected by the earth's internal heat-conduction and the NE-trending F4 fault and flows to the surface and is exposed as springs in the discharge area.