To provide handrail fitting structure allowing a handrail to be installed in an optional position from the surface side of a wall by after-fitting.

Handrail fitting structure comprises a reinforcing plate 3 having a fitting hole 3a and formed foldably at its folding part 3c, an attaching screw 4 provided with a cord body 8 at the tip of a leg part 4b, a holddown member 5 with a through hole 5a into which the leg part 4b is thread-fastened, and a handrail 7 jointed to the holddown member 5. The cord body 8 is passed through the fitting hole 3a, and the reinforcing plate 3 is folded. In this state, the attaching screw 4 and the reinforcing plate 3 are inserted into the wall back face side of an opening part 2 provided in a wall 1. The cord body 8 is pulled to pierce the fitting hole 3a and the opening part 2 with the leg part 4b, and the leg part 4b is thread-fastened into the through hole 5a to open the reinforcing plate 3. The peripheral edge of the opening part 2 is held by the holddown member 5 and the reinforcing plate 3 in the open state, and the handrail 7 is jointed to the holddown member 5.