Abstract: The commissioning of the 750 V DC traction system renovation project of Beijing Subway Line 5 needs to be carried out during the window, and the construction time for each window is only 2～3 hours. Due to the large number of commissioning items and the wide range of impact, it is particularly to make full use of the window time for the renovation project. By sorting out, sorting and summarizing the commissioning items and researching and summarizing the commissioning methods, the efficiency can be improved, the safety of subway operation can be ensured, and the commissioning work of future renovation projects can be provided with reference basis.