Abstract: The geological conditions of Zhangjihuai railway is complex,the structure and karst are extensively developed,and hence the risk of construction is high.Based on the construction of Zhangjihuai railway,this paper expounds the difficulties,prediction principles and key geophysical techniques of the railway tunnel geological prediction,and summarizes a set of technologies for the railway tunnel geological prediction.The practical examples show that the five-step method is useful in geological prediction,the surface exploration data are important for dividing the key sections for macroscopic control,the long-distance prediction and short-distance prediction of geophysical exploration technology should be used together,and the advance drilling must be used to verify the geophysical exploration anomalies,so that the prediction work can be a closed-loop, which is conducive to avoiding risks and reducing false reports.The whole set of advanced forecast technologies of Zhangjihuai railway is feasible and useful,which is worthy of spreading.