On March, "Monitoring and investigation technology research on mining activities in the first mining area of Sandaogou coal mine" project, undertaken by CCTEG Xi'an Research Institute passed the acceptance successfully. In this project, ground wireless micro-seismic monitoring system and underground KJ959 micro-seismic monitoring system are used to establish the "well ground" joint monitoring network for overburden mining in Sandaogou coal mine. The micro-seismic multi factor coupling comprehensive evaluation and early warning technology system for overburden mining in small coal mines around Sandaogou coal mine is preliminarily established. The successful implementation of the project of "monitoring technology for mining beyond the boundary around the mine" has expanded the application of micro-seismic technology and equipment in the field of coal mine micro-seismic monitoring. Especially the monitoring of coal mine underground boundary environment, plays an important role in prediction of illegal mining beyond the boundary. It can effectively protect coal resources and ensure coal mining safety.