Abstract: To address the issues of insufficient detection accuracy and low efficiency in identifying hidden hazard factors in red mud tailings ponds, this paper takes a red mud tailings pond of an aluminum industry in Shanxi Province as the research object and carries out a systematic application practice of the high-density resistivity method. The aim is to verify the method’s capability in identifying weak layers in the dam, anomalous stratigraphic sequences in the reservoir area, and structural risks in the surrounding environment. The study adopts the Wenner array to arrange measurement profiles covering key areas including the dam body, reservoir area, and adjacent mountainous regions. Based on regional geological conditions and the geoelectrical characteristics of rocks and soils, resistivity section reconstruction is performed using the least squares inversion algorithm. The results indicate: in the dam area, resistivity contours are gentle with no anomalies suggestive of weak interlayers or seepage channels; in the reservoir area, the red mud deposition layers show continuous low-resistivity characteristics with thickness increasing from south to north and no signs of uneven settlement; in the surrounding mountains, there is an overall high-resistivity background without responses indicative of fault fracture zones. The study confirms that the high-density resistivity method can accurately identify hidden hazards in red mud reservoirs, offering advantages of high resolution, superior efficiency, and low cost. The findings provide a low-cost, high-precision technical pathway for the safe operation and maintenance of industrial solid waste storage sites.