The invention relates to a wireless theft-and-damage-preventing monitoring and alarming method and system for electric power wells. Each electric power well is provided with a well cover state detector for detecting whether the corresponding well cover is in an opening or closing state, and each well cover state detector is respectively connected with a GPRS alarm and a GPS positioner. When a well cover is detected to be in an opening state under normal working conditions, the GPRS alarm sends an alarm signal to a monitoring center. The electric power well, of which the cover is under opening state, can be rapidly positioned through coding information of the electric power well and the GPS positioning system. Rapid alarm and accurate positioning of a well cover, of an electric power well, which is opened abnormally, are realized. The system has the advantages of low manufacture, installation and operation cost, sensitive detection and rapid and accurate positioning. The system and method are applicable to integral networking protection of urban electric power wells, and false alarm during normal maintenance can be prevented. The system and method are highly practical.