In 1952, the Electric Power Bureau of central Shandong area established a local electric power engineering department to be responsible for the demolition, installation and maintenance of power generator sets in Shandong Province. SEPCO originated from then.

In 1958, the Shandong Electric Power Bureau established a capital construction company called Shandong Electric Power Bureau Capital Construction Company, and set up the No.2 and No.3 construction department, design institutes, manufacturing and repair factory, and transmission line equipment factory under the company to be responsible for the construction of power projects in Shandong Province.

In 1985, various construction department under Shandong Electric Power Bureau Capital Construction Company were restructured into legal entities and expanded in scale, successively establishing SEPCO1, SEPCO2, SEPCO3, transmission & distribution engineering company, and nuclear power engineering company.

In 1992,Shandong Electric Power Bureau Capital Construction Company changed its name to SEPCO Electric Power Construction Corporation (SEPCO for short).

In 1998, SEPCO Nuclear Power Construction Group was established with SEPCO as the core, and it has seven wholly-owned subsidiaries including Shandong Electric Power Engineering Consulting Institute (now SDEPCI), SEPCO1, Shandong Electric Power Transmission and Distribution Engineering Company, Shenzhen Shandong Nuclear Power Engineering Company, Shandong Electric Power Pipeline Engineering Company, etc.

In 2011, the State-owned Assets Supervision and Administration Commission of the State Council established Power Construction Corporation of China (Power China), and SEPCO and its affiliated companies were incorporated under Power China.

In 2016,Power China successively completed the reorganization of SEPCO's asset relationship, and designated Ningxia Electric Power Engineering Company, Sichuan Electric Power Engineering No.2 Company, and Sichuan Electric Power Engineering No.3 Company as wholly-owned subsidiaries of SEPCO, and all the SEPCO's original subsidiaries were transferred out from SEPCO.

In 2017, SEPCO and its affiliated companies successively completed the corporate restructuring. The affiliated company Ningxia Electric Power Engineering Company was renamed Power China Ningxia Engineering Corporation Limited, and Sichuan Electric Power Engineering No.2 and No.3 Company were further integrated and renamed Power China Sichuan Engineering Corporation Limited.