To lay a rail for a sash sheave efficiently at a specified place.

In the laying method of the rail for the sash sheave, the lower end of leg pieces 14 are formed in rail structure having a piece 15 bent inwardly. A pair of wing pieces having elasticity are formed to the left and the right of a substrate 21 at that time, a plurality of fittings, to which stepped sections, with which the bent pieces 15 of the rail for the sash sheave are engaged, are formed, are fixed linearly at each lower end of the wing pieces at intervals on an underfloor ground surface at the place of the laying of the rail for the sash sheave, and the lower opening section of the rail for the sash sheave is fitted to a plurality of the fittings so that both wing pieces are narrowed from an upper section, and both bent pieces 15 are fitted to each stepped section of the fittings and the rail for the sash sheave is unified with the fittings.