Power is an important part of the energy industry, relating to national economy and people’s livelihood, and it is of great significance to ensure the security and stability in operation of power transmission and distribution system. Based on Wireless Sensor Network technology (WSN) and combined with the monitoring and operating requirements of power transmission and distribution system, this paper puts forward an application system for monitoring, inspection, security, and interactive service of layered power transmission and distribution system. Furthermore, this paper demonstrates the system verification projects in Wuxi, Jiangsu Province and Lianxiangyuan Community in Beijing, which have been widely used nationwide.