To construct a wooden building hard to fall because many fires and human damage occur after wooden buildings have fallen by a large earthquake.

A visually inconspicuous face of a structural member is cut with boundary lines to eliminate tenons of the wooden building, a T-shaped steel piece is inserted, a dovetail tenon is made in the longitudinal direction of the side face and a sash bar is fitted therein. A longitudinal through hole is bored in the center if a member by a drill or the like in the structural member with four conspicuous faces of the structural member to insert a shaped steel material. The structural member and the shaped steel member are inserted in the wooden joint and fixed by bolts. When a curved leaf spring is put in between the structural member and wooden joint, since violent vibration of an earthquake is altered to a gentle shake, its collapse can be prevented.