The present invention relates to a suspension device for a magnetic disk drive incorporated in an information processing device such as a personal computer, for example. This device has support plate devices 3, 7 that also serve as bracket arms, has a rigid body portion 13 and a spring portion 15 and loads a load on a contact 49 at the front end of the load plate, and is characterized in that, in this device, the support plate The board device 3, 7 is formed by at least two layers of boards 3, 7, the board thickness t2 of at least one side 7 of the boards 3, 7 can be etched to form a high-precision hole, and the pivot hole is formed on the board 7 having the board thickness t2 31. On the other side of the plate 3, a rotation fitting hole that is approximately concentric with the pivot hole 31 and has a larger diameter than the pivot hole 31 is formed. In this way, the flatness of the long floor portion and the accuracy of the pivot hole can be improved.