To provide a safe reform member bringing no defect such as color defect or wood grain defect of a sliced veneer, or the like among a plurality of different reform members, in natural precious wood decoration stairs and having no danger of stumbling in going up or down, as an existing stair can be very simply reformed by putting the member on the existing stair without removing the existing old stair and as the respective members of the upper face of treads, nosing part, risers, etc. can be continuously fitted.

The stair is reformed by covering the tread-board surfaces, nosings, the lower parts of the nosings, and risers with the reform members. A wood veneer is stuck on a relatively thin wood base material surface in the reform member. The reform member has a specified thickness, width, and length. Notches for bending works are formed in a plurality of specified positions of the reform member.