Abstract: The coal under the overthrust in Xisipo,Huaibei district was looked for with seismic,frequencial and transient domain electromagnetic soundings.The thickness of the overlay and the range of the overthrust have been qualitatively analysed.The theories and advantages and weakness of above three methods on the survey were simply recounted.It is thought that electromagnetic soundings has more efficiency on penetrating high resistive overlay and this has been proved by the raw curve,theoretic models and drilling.