Abstract: During the construction of large diameter gas drainage hole, ventilation hole, cable hole, transporting material hole, relief hole projects in coal mining areas, because of their special nature, it requires hitting target precisely , so it should control the well trajectory of the pilot hole strictly to ensure hitting target precisely. In the case of the large diameter relief well in PingShang coal mine, it will introduce the pilot hole of large diameter well precise hitting target technology, which can serve as a successful case.