PURPOSE: To obtain a truss structure having a sufficient mechanical strength by connecting a top part in the ridge piece direction in the horizontal direction and an inclined part corresponding to the slope of a roof in the ridge direction by a reinforcing brace part.

CONSTITUTION: A bent beam 100 is constituted of a top part 10 arranged in a ridge piece direction (in ordinary case, in the horizontal direction), inclined part 20 arranged with an inclination angle corresponding to the slope of a roof in a ridge direction, and a brace part 30 which connects the top edge part of the top part 10 and the top edge part of the inclined part 20. The top part 10 and the inclined part 20 are butt-joined by a means such as welding at one edge surface, and both the edges of the brace part 30 are joined with the side surfaces of the top part 10 and the inclined part 20 by a means such a welding. The top part 10 and the inclined part 20 are supported on a structure body such as a roof supporting body and an outside wall body through installation members 40 and 50.