Abstract: In order to control the water disaster area with the conceal sink hole, fault, cracks and other water flow structure possibly developed in No.216 mining bl ock of Xin'an Mine, based on an aquifer in Daqing limestone as a target layer, directional multi branch horizontal grouting boreholes were drilled at the surface ground, t he regional hydrologic exploration and full pre-grouting reinforced control were conducted and the basic mission of the Ordovician limestone water flowing channel of th e hydrological condition was completed.The water inrush probability of the seam floor was highly reduced and the safety of the underground roadway heading and the mining in the mining block was improved. There were 16 boreholes totally designed of the project. At present, the project has completed one main borehole, six branch b oreholes. The drilling horizontal section for up to 1 031 meters, the cement dosage of single hole reached 3 280 tons. The borehole quality and grouting quality were all met with the requirements of the mine owner and the grouting technical parameters were reached or over the relevant technical indexes.