Research conclusions: ( 1) During the geological survey，the high － density resistivity method should used for shallow section of the tunnel and the CSAMT sounding should be used for the deep － buried section of the tunnel for the advanced geological forecast to the ground surface． During construction，the geological survey method，TSP method and advanced boring should be used in tunnel for the advanced geological forecast． ( 2) Based on the various data of the advanced geological forecast of all phases obtained by all means，the forecast conclusion is draw up and the proposal on the construction is offered to direct the construction． ( 3) The work procedure of the advanced geological forecast is presented．