Abstract: The development and utilization of urban underground space inevitably results in soil erosion or soil subsidence in infrastructure construction, and the formation of underground "disease body" easily leads to the occurrence of urban road collapse. Taking the production project as an example, this paper introduces the geological radar method and shallow seismic exploration method to detect the drainage pipe network around the old urban area. The results show that ① the geological radar method can meet the detection requirements within the range of 7.0 m; ② In the case of complex site conditions, more interference need to be supplemented by shallow seismic exploration to detect. By using the above method, the location of underground "disease body" can be more accurately identified and the occurrence of road collapse can be prevented.