Abstract: Unknown gobs have always potential threats to work safety in coal mines, and there is a blind area when artificial seismic exploration is employed in gobs of coal mine of relatively shallow depth. To solve theses problems, this paper puts forward the basic theory and testing method of using the super ground coupled antenna (RTA50MHz) equipped with RAMAC/GPR to detect gobs of coal mines. Since coal seams and the gobs are too deep for ground penetrating radar to detect, the relationship between the resolution and the depth has to be considered. Proper parameters and modes of exploration have been employed to collect data. VC++ has been adopted and three-dimension has been developed for supplementary means of interpretation. Exact position of the target has been achieved and the exploration effect has been improved.