Combining with the untouched human-body detection sensor and wireless communication technology, a design and network architecture of electric power equipment guard against theft and alarm system based on General Packet Radio Service(GPRS) was introduced. It included the design of the self-adaptive human-body detection sensor, the communication method of GPRS-Data Terminal Unit(DTU), the solution of anti-collision technology about multi-point concurrent data, the realization of the power supply automatically switching circuit, the design and implementation of the system software functions, etc. The system was integrated with intelligence, high reliability and easy deployment. It can solve the problem of electricity installations guard against theft and will be very popular for power industry.