Abstract: With the rapid expansion of the scope of urban construction, the near-surface geological structure is more and more complex. The conventional drilling method is difficult to meet the needs of the foundation exploration. For this reason, based on theory of complementary advantages, a new idea inversing apparent resistivity by the transient electromagnetic data under the constraint of drilling data is put forward, which combines the advantages of the transient electromagnetic method(TEM), such as high space sampling rate, rich geological information, accurate determining of lateral boundary of geological body and so on, and the advantages of drilling, such as high precision vertical sounding, accurate layering and so on. A new interpretation method of TEM data based on drilling constraint is given, which can better overcome the limits of traditional TEM method to get high accuracy depth results difficultly and improve the depth explain ability of calculating apparent resistivity section. The goaf detection results in Haojinyuan house construction area show the new interpretation method can obtain good effect, which determine a coal goaf water area about 0.01 km² in the central section, and a non-goaf area about 0.009 75 km² in the mid-east region, and infer other region are coal goaf area.