The present paper deals with some problems concerning the detection of coalfield depressed pillars with the high-density electrical method. The boundary element method was used to simulate the influence caused by variation in various factors of the depressed pillar upon the geoelectric anomalies, and the method for delimiting the depressed pillar is given.In view of the grave geoelectric interference that exists in the ore district, the paper suggests some technical measures for data collecting and processing. The results of the application show that the high-sensity electrical method can be used effectively to detect coalfield depressed Pillars.