Abstract: The computer monitoring system of Xitang River diversion project consists of several subsystems such as computer centralized control subsystem, local monitoring subsystem, video security subsystem, water quality monitoring subsystem and information management subsystem, and the subsystems were connected together by main optical fiber fast network. The design principle, the structure, the system software, the security measures and the operation management of the network were introduced.

Key words: water conservancy project, computer monitoring system, optical fiber fast network, network security