As the development of mining technology and increasingly depth of mining, goaf water area settlement becomes the key of water prevention and control. Direct current polarization sounding was adopted to explore in Tashan Mine, based on the analysis of apparent polarization sounding curve, testing point exceeds 100 m, the curve with abnormal high value, the maximum of ηs 2%, that is strong water richness, the circled area is water. Besides, the water volume was calculated by the measurement of water area and average thickness of coal seam and pressure parameters, which benefits the exclusion of water area and safe mining.