Research conclusions: According to the situation that there are many restraints factors on the project of the power supply of the substation for high － speed railway，this paper puts forward the safe，reliable，economic and applicable design principle for the power supply project，describes the short － term and long － term relations between the power supply capacity and the power demand and the relation between the power supply project and the investment for the pipes and digging ditches by the city，and introduces the key points and mattes for caution in the design． Especially this paper offers four design schemes of using traction power for the power supply to the large railway station building and railway terminal and it can provide the reference to ensuring the construction completion and strengthening the control of project cost．