The invention discloses a variable-cross-section wall type vertical supporting structure used for the reverse construction method and a construction method of the vertical supporting structure. The supporting structure comprises a basement wall body and a wall type foundation. The basement wall body comprises a basement wall body steel reinforcement cage and basement wall body concrete and has a first thickness. The wall type foundation comprises a wall type foundation steel reinforcement cage and wall type foundation concrete. The wall type foundation extends downwards from the bottom of the basement wall body and has a second thickness. The second thickness is larger than the first thickness. The joint of the basement wall body and the wall type foundation is the basement bottom plate top elevation position. The section, bearing capacity and rigidity of the wall type foundation of the supporting structure are all higher than those of a conventional foundation, and it can be ensured that the upper structure can be constructed without being limited by the height during reverse construction. In addition, after the concrete is poured, only a formwork in a basement needs to be detached in the later period when the basement is dug to the elevation, the wall body chiseling work is avoided, the supporting structure is green and environmentally friendly, cost is saved, the construction period is shortened, and multiple purposes are achieved at one stroke.