To provide a remaining reinforcing member for preventing the deformation of a post hole of a concrete structure.

The remaining reinforcing member 10 embedded in the post hole of the concrete structure includes a coil-like wire 10a and spacers 11a stuck to the wire at spaces. The spacer has a through hole 11c for inserting the coil-like wire through. The remaining reinforcing member may have spacers stuck onto rings at spaces by forming a wire in circular shape, cutting off a part thereof to form a ring formed with an eliminated part 13a, sticking a plurality of rings at spaces in the height direction of a post 13b so that the eliminated parts face the same direction, and sticking the spacers onto each ring at spaces. The remaining reinforcing member may also have bent parts 14a instead of the spacers by forming a wire in coil shape, and bending the wire in angle shape to the inside of the coil.