A turbo fan comprising: a main plate having a disc shape and on which a rotational shaft is mounted; a side plate provided to be separated from the main plate along an axial direction of the rotational shaft and having a ring shape with an opening at a center portion of the side plate; and a plurality of wings fixed between the main plate and the side plate along a circumferential direction of the main plate, wherein each wing of the plurality of wings includes a leading edge having a portion coming in contact with the side plate, a trailing edge, wherein a cross-section of each wing in a plane perpendicular to the axis of rotation comprises an airfoil with a central line extending between the leading and trailing edges, the cross-section comprising a bended portion, which is bended in a reverse direction against a rotational direction of the wing, wherein the central line comprises a front end having a first curvature between the leading edge and the bended portion, and a rear end having a second curvature between the bended portion and the trailing edge, which is different to the first curvature, wherein the curvature of the central line is discontinuously varied at the bended portion; and wherein the leading edge has a main plate contact portion at which the leading edge and the main plate come in contact with each other; the leading edge has a side plate contact portion at which the leading edge and the side plate come in contact with each other; and characterized in that the bended portion is located more outward in an outer diameter direction as compared to the side plate contact portion. a main plate having a disc shape and on which a rotational shaft is mounted; a side plate provided to be separated from the main plate along an axial direction of the rotational shaft and having a ring shape with an opening at a center portion of the side plate; and a plurality of wings fixed between the main plate and the side plate along a circumferential direction of the main plate, wherein each wing of the plurality of wings includes a leading edge having a portion coming in contact with the side plate, a trailing edge, wherein a cross-section of each wing in a plane perpendicular to the axis of rotation comprises an airfoil with a central line extending between the leading and trailing edges, the cross-section comprising a bended portion, which is bended in a reverse direction against a rotational direction of the wing, wherein the central line comprises a front end having a first curvature between the leading edge and the bended portion, and a rear end having a second curvature between the bended portion and the trailing edge, which is different to the first curvature, wherein the curvature of the central line is discontinuously varied at the bended portion; and wherein the leading edge has a main plate contact portion at which the leading edge and the main plate come in contact with each other; the leading edge has a side plate contact portion at which the leading edge and the side plate come in contact with each other; and characterized in that the bended portion is located more outward in an outer diameter direction as compared to the side plate contact portion.