Abstract: There is a high possibility of water seepage accident in roadway excavation in Gubei coal mine. In order to tunnel efficiently and safely, it is necessary to explore the floor limestone in a certain range of the two sides of the roadway in advance. Taking boreholes (TD2-1 and TD2-2) as examples, the construction technology of advanced exploration directional drilling is analyzed and optimized in this paper. Then, the author takes the conventional advanced exploration hole in the same area as the comparative object, and makes a comparative study of the two construction schemes from economic benefit and effect of exploration. The results show that, compared with the conventional advanced exploration borehole, directional advanced exploration hole has higher economic benefit and exploration effect. This is expressed in the latter requires less drilling and auxiliary excavation work, but has higher drilling rate in the target horizon.