In a vehicle body component (10), a bent portion (38) that is formed in a component main body (34) made of a metal plate is formed of a thickened portion (46), in which a plate thickness of the metal plate (36) as a material of the component main body (34) is gradually increased. Just as described, since the bent portion (38), on which stress is likely to be concentrated when a load is applied to the component main body (34), is formed of the thickened portion (46), a plate thickness of a portion where the stress is not concentrated can be prevented from being increased more than necessary. This can contribute to improvement of mass efficiency.