The invention discloses a wiring pole for a substation cable trench and a usage method of the wiring pole. The wiring pole structurally comprises multiple sections of wiring pole bodies which are connected end by end, wherein the wiring pole bodies are straight poles with square cross sections; and every two adjacent wiring pole bodies are connected through a foldable connector. After the wiring pole for the substation cable trench is used, only one concrete cover plate is required to be lifted up at the intervals of about 20 meters or as required, not all cover plates are required to be lifted up, manpower consumption is reduced greatly, the wiring pole is easy to use, wiring is rapid, the wiring pole is applicable to a narrow cable trench, and the cable wiring efficiency can be fully improved.