Abstract: Introduction The coal-electricity integration mode is a development direction of coal-fired power plant in recent years, some planning power plant built in the coal mined area, the goaf is a big threat to the safety of power plant, and goaf detection is the basis of evaluation and treatment, so the goaf detection is a very important work. Method According to the characteristics of the goaf in Guizhou Dafang coal-fired power plant, the comprehensive geophysical exploration technology in coal mine goaf detection, overcome the single geophysical technology shortcomings. according to the electrical and elastic geological differences, using the method of high density resistivity method, transient electromagnetic method and seismic imaging method combining the development of goaf detection. Result Through comprehensive interpretation of geophysical technology, this work provide achieved good results, gives the goaf roadway and the spatial distribution and drilling verification, and accumulated experience for the subsequent detection of the integration of coal power plant in the goaf. Conclusion The detection of goaf need to choose the geophysical techniques which based on the topography, geological features, and geophysical characteristics of the coal mines, and a variety of methods should be tested to give full play to the advantages of each method, so as to obtain an actual detection result.