To provide brace fitting for composing the corner part of the framework of a timber construction framework structure building that can sufficiently resist not only force in a horizontal direction but also force in a torsional direction.

When two members crossing at right angles in the timber construction framework structure building, for example, a girder 5 and a beam 7 orthogonally crossing the girder 5, crossing beams, or the like are joined or reinforced, arrangement is made so that a rib part 9 of brace fitting 1 is parallel with a plane that is formed by the members 5 and 7, and installation flanges 11 and 13 that are provided at right angles to the rib part 9 over the entire length at two-side positions that cross each other at the rib part 9 are installed to each of the members 5 and 7 via a hole 17 for joining by a joining means 15.