Abstract: In order to improve the accuracy of three-dimensional high density electrical method for water exploration in coal mine, the present method is improved. The three-potential electrode system is selected as the electrode device to realize the automatic closing of the instrument during data collection and enrich the information of the data body. In order to improve the precision of inversion, the shallow vertical subdivision 3D model is selected. The least squares method with double constraint of inequality constraint and smooth constraint is selected as the inversion method. In the calculation method, the Jacobian iteration diagonal matrix is used. The 3D data volume of stratum roof and floor can be obtained by stereo visualization processing. By slicing technique, the water-rich properties of roof sandstone stratum, bottom three limestone strata and Datun fault zone are obtained so as to ensure the safety of coal mine production.