To maintain a decrease in groundwater level as low as possible in the ground, shorten the period of construction work, and reduce construction costs by shortening the setting depth of a retaining wall and reducing the setting depth rationally even in a vertical shaft having a high coefficient of permeability in a vertical shaft having a great depth.

This vertical shaft construction method comprises a precedence ground beam process in which a ground beam 11 is constructed in the ground 1, a process for constructing a retaining wall 12, an underwater excavation process in which water 14 is introduced to the inside of a vertical shaft 13 surrounded by the retaining wall 12 and the inside of the vertical shaft 13 is excavated underground up to the ground beam 11, a temporary concrete placing process in which underwater concrete is placed on the ground beam 11, a drain process for draining water 14 from the inside of the vertical shaft 13, and a final concrete placement process in which the final concrete is placed on temporary bottom slab concrete 15 formed by the temporary concrete placement and on the inner surface of the vertical shaft 13. In the precedent ground beam process, a mechanical agitating method or a high pressure jetting agitating method is used for the construction of ground beam 11 in the precedent ground beam process.