Abstract: The surrounding rock pressure is obvious when the -850 main cross-hole in Qianjiaying Mine of Kailuan Group constructs to 774 m position. In the process of advanced exploration of the occurrence conditions in 5 coal seam, the holes are spraying and the gas is abnormal. In order to do a good job of “outburst prevention”, Qianjiaying Mine has carried out geotechnical safeguards work of -850 main cross-hole, including precision control measurement, dewatering and depressurization measures, geological and gas geology detailed investigation and so on, which constructs an outburst prevention technical support system suitable for the regional characteristics of Qianjiaying Mine.