Geological conditions in Yunnan mountainous area are complex, and geological hazards such as water and mud inrush often occur in tunnel construction. Tunnel geological prediction is an important way to prevent geological disasters in tunnel construction. The rational layout and implementation of advance exploration drilling can effectively reveal the geological conditions in front of the tunnel face and prevent the occurrence of geological disasters. Nevertheless, for the irregular geological bodies such as karst, the limited 1~2 advance exploration drilling holes sometimes fail to reveal these geological bodies and cause major safety risks to the tunnel construction. It is of great significance to make full use of the advanced geophysical prediction data, especially the TEM which can guide the layout of the advance exploration drilling holes and have the great significance for improving the prediction effect. In this paper, taking the Yangwu tunnel of Yumo railway as an example and based on the analysis of TEM, the authors successfully guided the advance exploration drilling layout, and then compared the results with the drilling and construction excavation results. It is shown that the TEM is effective in predicting and guiding the advance exploration drilling. Some suggestions are given concerning the employment of TME combined with advanced horizontal drilling in the future.