Some unknown structures are always uncovered and gas outburst or water bursting can easily take place during the tunneling of mine roadways rich in gas or water, which seriously influences the safety in coal mine production. On the basis of the theory of whole space "smoking ring effect" of the mine transient electromagnetic method (MTEM) in roadway and according to the limited space around the roadway head and the exploration environment of the interference of other metal facilities, the authors chose MTEM to detect geological structures in front of roadway head, and systematically studied the detection devices as well as detection and graphical display techniques of advanced detection of MTEM in tunneling mine head. Practical application shows that the exploration results are well consistent with the uncovering situation of the roadway