The features and advantages of optical transport network (OTN) technology is discussed in this paper. Taking power network in Hubei Province as an example, the status and characteristics of OTN in power system are analyzed, and a new technology was introduced to further optimize the existing network structure. The original synchronous digital hierarchy (SDH) transmission system is replaced by the new OTN system in provincial main power transmission network, which could improve the bandwidth and safety of the network, meet the needs of smart grid and operation management, as well as ensure the reliable and efficient transmission of business information.