To provide a tool capable of being suitably used for bending a building hardware.

A building hardware bending tool T is so constituted that a holding section 3 is provided to the lower part of a tool head, and a thrusting body molded by combining with arms 2 and 2 is provided on both sides of the holding section 3 in a rotatable manner. A tongue piece-shaped plate 7b of a building hardware 7 is inserted in the holding section 3, and when the arms 2 and 2 is rotated so as to open them, the thrusting body is rotated downward from a vertical straight posture with both sites of the holding section 3 as the fulcrum, engaging vanes 7d and 7d are pushed down, and as a result, the engaging vanes 7d and 7d are bent.