PURPOSE: To provide building structure combining an X-steel-frame construction strong against destruction and lumber by means of improving an aseismatic property by using an X-steel-frame material for centers of main pillar and beam and combining it with a conventional wooden architecture.

CONSTITUTION: A building structure combining an X-steel-frame construction and lumber is formed by connecting an X-steel-material pillar 1 having four cross sectional legs and an X-steel-material beam 12 having four cross sectional legs to each other so that each of the legs makes an angle of 45 degrees relative to a wall surface in the case of the X-steel-material pillar 1 and each of the legs makes an angle of 45 degrees relative to a floor surface in the case of the X-steel-material beam 12. It is constituted by connecting a triangle molded material to the X-steel-material pillar 1 or the X-steel-material beam 12.