Smart grid is the core of smart city, and distributed energy is the main component of smart grid development. As distributed energy access to power grids requires more and more power grid stability, in order to ensure the security and reliability of distributed energy generation and consumer electricity, it is necessary to construct a complete distributed energy monitoring network. At this time, it is urgent to adopt the secure, reliable, flexible and real-time two-way communication mode to carry the access of large-scale monitoring equipment. At this point, 5G wireless communications have higher spectral efficiency and massive connectivity due to the growing demand for Mobile Internet and Internet of things. Therefore, this paper discusses the mMTC technology, which is one of the 5G application scenarios under the smart grid distributed energy regulation. The technology has the characteristics of small data packets, low power consumption and massive connection, which makes up for the shortage of the existing technology in the number of terminal connections. It provides a new solution for the integration of smart grid and Internet of things technology in the important links of intelligent grid, such as equipment detection, information collection and measurement automation.