Abstract: In order to accurately explore the goaf distribution and water richness characteristics of coal mines, and provide quantitative basis for mine water disaster prevention and control, taking Yungaishan Coal Mine as the research object, combined with the previous geological exploration data, the small wireframe overlapping loop line transient electromagnetic method is adopted to conduct ground detection. A testing network is set up and data are collected through the Terra TEM transient electromagnetic exploration system, the apparent resistivity characteristics of No. 1 and No. 2 coal seams are obtained through processing and inversion. A quantitative threshold for apparent resistivity determined by water richness is established, and the electrical property differences of different low resistivity anomalies such as goaf water accumulation, fault water conductivity, surface permeability and others are clarified, the range of goaf and water-rich areas are accurately delineated. The results show that there are only 8 small types of goaf water accumulation areas developed in the research area, with a relatively small total area and concentrated in the eastern region, which have limited impact on the overall subsequent mining; The spatial correspondence and quantitative characteristics of the drilling verification results and the detection results of transient electromagnetic method are highly consistent, confirming that this method has technical feasibility in detecting water richness in multi-coal seam goaf, the established quantitative determination criteria can provide reference for similar mine water disaster prevention and control and detection.