To ensure the operation of the North China Power Grid safely, economically and qualitatively, it needs to establish and put North China power dispatch data network into operation. According to the three-tier network structure, the core and backbone layers adopt ring structure, the access layer adopts double star structure. It sets the network management center in the dispatching and communication center, runs the network and operations management uniformly. With three hierarchy and IP technology adopted and data communication network with high bandwidth and performance constructed on the highly reliable optical fiber transport channel, the North China power dispatch data network can meet the requirement of related business for data transmission. The design of the data network is analyzed in the aspects of network topology, IP layout, MPLS VPN, network security, and network management.