Abstract: In order to achieve the telemetry, remote signal, remote control, remote adjustment functional requirements of mine underground relay protection monitoring system, design the underground network communication of the system.In accordance with the requirements of power system communications, design Profibus-DP bus architecture.According to profibus DP Bus communication protocol, we give the system software design.We give the structure of the entire underground monitoring system, the system's hardware architecture and software.

Key words: Mine Underground, Relay Protection System, Profibus DP