STRUCTURAL MEMBER FOR AUTOMOBILE BODY

A deformed part in a case in which the application of a collision load causes bending deformation in a structural member for an automobile body having a hardness distribution (strength distribution) composed of a quenched part, a base metal hardness part, and a transition part in a longitudinal direction is used as the base metal hardness part to avoid plastic strain concentration in the quenched part. This structural member for an automobile body has a hollow steel main body having a rectangular cross section. The main body includes a quenched part, a base metal hardness part, and a transition part in this order, in at least a part thereof in an axial direction. The length (L) of the transition part as related to the axial direction satisfies the relationship of 0.006 (mm -1 ) < LA/I ¤ 0.2 (mm -1 ) in a case in which the cross-sectional area of the main body is (A) and the moment of inertia of area is (I).