A supporting member includes a first plate portion including a supporting surface, a first hole, and a female thread portion formed at an inner peripheral surface of the first hole; a second plate portion provided by hemming the metal plate member; a third plate portion provided by bending the metal plate member at one end portion of the second plate portion at substantially a right angle; and a second hole continuing between the second and third plate portions so that the screw threadably engageable with the female thread portion is prevented from interfering with the second and third plate portions. The second and third plate portions provide a bent portion therebetween positioned within a range of a nominal diameter of the female thread portion with respect to a thickness direction of the third plate portion, as seen in a direction perpendicular to the thickness direction.