A front subframe 42 is formed of an aluminum alloy into a frame that is formed substantially into a shape of parallel crosses or into a rectangular shape and is made up of left and right front joint portions 64, 64 and left and right rear joint portions 71, 71 which are disposed at corners of the frame that is formed substantially into the shape of parallel crosses or the rectangular shape, and left and right longitudinal members 61, 61, and front and rear cross members 62, 67 which connect the joint portions 64, 64, 71, 71 together. The left and right front joint portions 64, 64 and the left and right rear joint portions 71, 71 are formed of an aluminum alloy die-cast product, whereas the left and right longitudinal members 61, 61 are formed of an aluminum alloy wrought product. In addition, connecting locations 76 . . . of a camber angle adjusting mechanism 157 are formed of an aluminum alloy die-cast product. Additionally, a rear cross member compound 63 is formed of an aluminum alloy die-cast product.