State Grid and China Southern Power Grid are parallel and not subordinate to each other. In the past, they were called the Ministry of National Electricity. In 2002, State Power Company reorganized and established two major power grid companies, State Grid Corporation and China Southern Power Grid Corporation, and five major power generation companies (Guodian, Huadian, Datang, CIC and Huaneng). Among them, State Grid Corporation North China Branch, State Grid Corporation East China Branch, State Grid Corporation Central China Branch, State Grid Corporation Northeast Branch, State Grid Corporation Northwest Branch and State Grid Corporation Southwest Branch all belong to State Grid subsidiaries. South China is divided into Southern Power Grid, which is the same as the State Grid and directly controlled by SASAC.

State Grid and China Southern Power Grid are responsible for the operation of the national power grid, of which State Grid is responsible for 26 provinces and cities and China Southern Power Grid is responsible for 5 provinces including Guangdong. These two companies account for about 89% of county-level electricity sales in China.

The main difference between the two is the different jurisdiction:

The core business of State Grid Corporation is to invest in power grid construction and operation, and its business area covers 26 provinces, autonomous regions and municipalities directly under the central government, covering more than 88% of the country's land area.

China Southern Power Grid Corporation (hereinafter referred to as China Southern Power Grid Corporation) is a super-large state-owned power grid enterprise officially listed on February 29th, 2002, covering five southern provinces (regions) such as Guangdong, Guangxi, Yunnan, Guizhou and Hainan.