Abstract: The mass concentration of the pollutant in the underground water of the 15^＃ shaft in a gold-dressing plant exceeds the standards. So a high-density electricity method is used to investigate the underground water pollution source and determines the No.2 tailings pond to be the pollution source of the underground water of the 15^＃ shaft. That provides guidance and a basis for the implementation of the next-step renovation scheme. The underground water seepage channels and pollution sources obtained from the high-density electricity method investigation agree with the data from hydro geological data and the detection data of each monitoring shaft， suggesting that the high-density electricity method is an effective technical way to look for pollution sources worth promoting.