A frame member comprising a corner section extending in a lengthwise direction and a side wall section extending from a widthwise end of the corner section, wherein a softening layer is provided in a sheet thickness direction so as to present on a surface of the corner section on at least one of a bending inner side and a bending outer side, the softening layer extends along the side wall section from the corner section to an area having a length longer than or equal to half a widthwise length of the side wall section, a hardness of a sheet-thickness-direction central section in a portion where the softening layer is provided is greater than or equal to 400 Hv, and the softening layer is an area having a hardness smaller by at least 10 Hv than the hardness of the sheet-thickness-direction central section in the portion where the softening layer is provided, a thickness of the softening layer is greater than or equal to 2% of the sheet thickness in the portion where the softening layer is provided but smaller than 20% of the sheet thickness in the portion where the softening layer is provided, the hardness of the softening layer at the surface is greater than or equal to 0.5 times the hardness of the sheet-thickness-direction central section in the portion where the softening layer is provided but smaller than 0.9 times the hardness of the sheet-thickness-direction central section in the portion where the softening layer is provided, the softening layer has a first hardness changing area that is an area extending from the surface to 40% of the thickness of the softening layer in the sheet thickness direction and a second hardness changing area that is an area different from the first hardness changing area out of the softening layer, an absolute value ΔHv1 of a change in hardness of the first hardness changing area in the sheet thickness direction is greater than an absolute value ΔHv2 of a change in hardness of the second hardness changing area in the sheet thickness direction, and R/t≤2.5 is satisfied, where R represents a bending radius of the corner section, and t represents the sheet thickness of the corner section. wherein a softening layer is provided in a sheet thickness direction so as to present on a surface of the corner section on at least one of a bending inner side and a bending outer side, the softening layer extends along the side wall section from the corner section to an area having a length longer than or equal to half a widthwise length of the side wall section, a hardness of a sheet-thickness-direction central section in a portion where the softening layer is provided is greater than or equal to 400 Hv, and the softening layer is an area having a hardness smaller by at least 10 Hv than the hardness of the sheet-thickness-direction central section in the portion where the softening layer is provided, a thickness of the softening layer is greater than or equal to 2% of the sheet thickness in the portion where the softening layer is provided but smaller than 20% of the sheet thickness in the portion where the softening layer is provided, the hardness of the softening layer at the surface is greater than or equal to 0.5 times the hardness of the sheet-thickness-direction central section in the portion where the softening layer is provided but smaller than 0.9 times the hardness of the sheet-thickness-direction central section in the portion where the softening layer is provided, the softening layer has a first hardness changing area that is an area extending from the surface to 40% of the thickness of the softening layer in the sheet thickness direction and a second hardness changing area that is an area different from the first hardness changing area out of the softening layer, an absolute value ΔHv1 of a change in hardness of the first hardness changing area in the sheet thickness direction is greater than an absolute value ΔHv2 of a change in hardness of the second hardness changing area in the sheet thickness direction, and R/t≤2.5 is satisfied, where R represents a bending radius of the corner section, and t represents the sheet thickness of the corner section.