The high bandwidth and low latency of 5th generation mobile networks (5G) play an important role in the construction of ubiquitous power Internet of Things (UPIoT), and provide strong protection for the goal of universal interconnection and human-computer interaction. This paper studies the application of 5G in UPIoT. Firstly, the mainstream IoT communication technology at home and abroad is summarized, the principle and characteristics of 5G are introduced emphatically. Secondly, the characteristics of UPIoT and the demand for communication services are analyzed deeply. The three major application scenarios of 5G and the possible power business of each scenario are studied. Thirdly, the application of 5G in the ubiquitous power Internet of Things is studied from the aspects of grid-connection of distributed new energy and energy storage, monitoring of power transmission and transformation operation, regulation and protection of distribution network, user load perception and regulation, collaborative scheduling and stability control, planning and investment, and comprehensive governance. Finally, the key technologies of 5G applied to the ubiquitous power Internet of Things are discussed from the aspects of power generation, transmission, substation, power distribution and power consumption, and the 5G network security protection technology is studied. 5G has broad application prospects in UPIoT, and has important engineering application value.