According to one embodiment, a magnetic disk device includes a magnetic disk, a spindle motor, a magnetic head, a ramp load mechanism, a filter, and a control section. The control section rotates the spindle motor at a second rotating speed for a given period of time at startup of the device, and then loads the magnetic head from the ramp load mechanism to a prescribed position on the magnetic disk. The second rotating speed is higher than a first rotating speed at which the spindle motor is rotated at the magnetic head reads/writes data from/to the magnetic disk.