To increase the maximum load of a hollow bent member.

The bent member 1 satisfies the relationship of 0.55<h/H<0.85 (condition α) and 0.5<δ/t<4 (condition β) when the distance between the first and second walls is defined as H, the distance between the first wall and a bent part as h, the distance between both end parts of the first and second walls in the direction perpendicular to the direction that both walls face each other as δ, and the thickness of the second wall as t. According to this constitution, when the bent member 1 is compressed in a direction (Y direction) that a first wall 11 and a second wall 12 are opposite to each other, force is added to the bent member 1 in the direction that the respective bent parts 22, 26 of a pair of side wall parts 20 enter the inside of the cross sections. The force by which the side wall part 20 is intended to expand to the outside of the cross section is negated to allow the side wall part20 to hardly bulge to the outside of the cross section. Thus, the maximum load of the bent member 1 is increased.