PURPOSE: To prevent the weight of an elevator from being imposed directly on a building, by carrying respective structural member of a steel tower hoistway into a building as a single component or a temporary assembly, and assembling the steel tower hoistway with a desired height using connecting frame members.

CONSTITUTION: Steel tower columns 22 are erected from the four corners of a base frame member 20, and at its top end, a top frame member 24 supporting a machine table of a machine room is provided. The steel tower columns 22 are formed by connecting two long members connected through a connecting member 29 respectively, and connected to each other. A horizontal member 26 is constituted of an entrance sill corbel 26a, a pair of guide rail supporting member 26b, and a rear member 26c, and these members are fixed to the steel tower columns 22 through mounting members 30. The top frame member 24, the horizontal frame member 26, and connecting member 28 are mounted so as to support interconnection among the steel tower columns 22 and keep their intervals constant. It is thus possible to support the load of the elevator sufficiently.