Provided is high-speed train transformer substation main wiring construction based on a three-set single-phase traction transformer. The traction transformer substation main wiring construction is optimized, and on the premise that a wiring form and an operation method meet the requirements of high-speed railway operation, the number of equipment and construction investment are reduced. The main wiring construction comprises a three-phase external incoming power line, a high-pressure side busbar, traction transformers and a 27.5 kV side busbar. The three-phase external incoming power line is composed of a first incoming line and a second incoming line, and conducts wiring with the high-pressure side busbar in traction transformer substation. The traction transformer is composed of a first traction transformer, a second traction transformer and a third traction transformer, the high-pressure sides of the first traction transformer and the third traction transformer are connected to the high-pressure side busbar through a group of disconnecting switches and a circuit breaker respectively, the high-pressure of the middle second traction transformer is connected to the high-pressure side busbar with different phase sequences through the circuit breaker and two groups of the disconnecting switches. A 27.5 kV I section busbar, a 27.5 kV II section busbar and a 27.5 kV III section busbar are formed on the 27.5 kV side busbar through the two disconnecting switches in a segmented mode, and the low-pressure sides of the first traction transformer, the second traction transformer and the third traction transformer are connected to the 27.5 kV I section busbar, the 27.5 kV II section busbar and the 27.5 kV III section busbar separately through a group of the disconnecting switches and the circuit breaker.