Currently， the main protection used in the high-voltage power system is mainly the pilot protection based on power line carrier communication while the backup protection makes decisions with local information. This paper analyzes the problems exiting in the pilot protection and the traditional backup protection. Considering the advantages of fiber optic communication， a new hierarchical region protective system is proposed， which locates a fault by sharing electric information transmitted through optic fiber. By working in collaboration with the pilot protection and the backup protection， it can further strengthen the first line of defense of the power system. A detailed description is made of the structure and the work process of the region protective system. The principles of the zero and negative sequence directional protection and synthetic fault phase selection are dealt with. Many types of fault have been simulated with EMTP， especially the complex faults inside and outside the region， with the correctness of the region protective system verified by the results.