Abstract: For problems of blind spot, incorrect description and not in time transmission of information existed in coal mine hidden danger investigation system, handheld terminals were applied in closed-loop management of hidden danger. Functions and specific application of the handheld terminal in hidden danger reporting, governance reply, field rechecking were described. Relevant suggestions for application of the handheld terminal in underground were given, including establishment of hidden danger information database and location of hidden danger place. The application of the handheld terminal improves traditional working mode and realizes real-time, accurate and visual management of hidden danger investigation.