In a fan blade of a turbofan engine and a method for determining a shape of the fan blade, a shape from a blade root of the fan blade up to a predetermined position in a span direction of the fan blade is same as a shape from a blade root of an original fan blade up to a predetermined position in a span direction of the original fan blade, and a shape from the predetermined position in the span direction of the fan blade up to a blade tip thereof is a shape formed by rotating, only by a predetermined angle in a direction opposite to a direction of rotation of the fan blade with a rotating shaft as a center, each of blade elements present from the predetermined position in the span direction of the original fan blade up to a blade tip thereof.