To provide an anchor which reduces the damage of a plate-like body and enhances anchoring effects, and a construction method for nipping an anchor.

An anchor 1 comprises a cylindrical sleeve 11 which is open at both longitudinal ends and provided with a flange 112 at one end and a plurality of expanding slots 114 extending from the other end along the longitudinal direction, an insertion member 12 which is inserted from the side of the flange 112 into the inner circumference of the sleeve 11 to expand the diameter of the sleeve 11 and a nipping member 13 which is provided with a through-hole through which the sleeve 11 is fitted, wherein the sleeve 11 bites into the plate-like body 3 due to the diameter expansion of the sleeve 11, and the plate-like body 3 is nipped between the flange 112 and the nipping member 13, thus resulting in the possibility to secure fixedly an attachment member 2 to the plate-like body 3 by anchor effects enhanced by two actions including the biting into the plate-like body 3 and nipping in the anchor 1.