To provide a wiring accessory installation body that achieves drawing out of cables from an existing wiring accessory installation place and installing of additional wiring accessories, by using only one type thereof.

A wiring accessory installation body 1 includes a frame body 10 formed in a square frame shape. The frame body 10 includes: fixing parts 13 detachably formed thereon for fixing a wiring accessory; and attachment parts 15 into which fixing members for attaching the frame body 10 onto a wall surface are inserted. The frame body 10 is formed with such a thickness that: by fixing the frame body 10 on a wall material to cover a penetration hole formed on the wall material, a part of the wiring accessory is housed in a penetration hole; and by stacking the frame bodies 10, the wiring accessory is housed in the stacked frame bodies 10.