Abstract: Influenced by complex terrain conditions, it is difficult for research of geophysical prospecting to rapidly and accurately detect gob without water in abandoned mines. Through the study of transient electromagnetic method for the application of hydrologic geophysical detection technology in coal mines, the advantage of the characteristics of method is less affected by terrain, to avoid sensitive reaction of the ideas of low resistance body, choosing a small launch wire frame, high frequency, suitable time windows, the exploration work finally completed on the gob without water in the complex terrain that other geophysical prospecting methods can't construction areas. Through summarizing the reflect characteristics of high resistance electrical of the detection data, and infer the gob without water scope. Detection results have been verified in the tunneling period, which shows that the transient electromagnetic method can be used for gob detection of high resistivity in the mines.