Abstract: Existing status of power off control in coal mine underground was introduced, network structure and working principle of interactive power off control by hand-held wireless mobile terminal were described, main test interface and performance of interactive control system of hand-held wireless mobile terminal were given, and some disaster ranges were discussed in which commands of wireless power off were needed to be given in time. Using hand-held wireless mobile terminal to control power off in coal mine underground can make workers to know disaster's change and range in coal mine underground in time and dynamically without limitation of time and space, then commands of wireless power off can be given and executed in time so as to cut off power supply in underground and prevent accidents to happen and disaster to expand.