The invention is a clearance-type waking up method of a wireless meter reading system, comprising the following steps: transmitting a pulse every second to a wireless communication chip by a microprocessor in a wireless collection terminal; placing the pulse into an information collection register in the wireless communication chip; judging whether the same frequency signal having the same overlapping with the work frequency of 470MHz exists or not in monitoring time, if not, the wireless communication chip being at dormant state, if so, sending back a response pulse to the microprocessor by the wireless communication chip; sending a directive for waking up the wireless communication chip quickly and leading the wireless communication chip at work state. The invention solves the problems of large energy consumption of repeatedly waking up of the wireless collection terminal, same frequency inference and small distance of meter reading in existing wireless meter reading system.