To read the data while keeping a read speed that vibration in a digital disk becomes a vibration level without adversely affecting the read of the data.

This device is provided with a vibration detection part 4 outputting a vibration detective signal 34 when a level of an AC component of a tracking error signal 31 showing a follow-up state of a track exceeds a prescribed level, and a rotation control part 7 controlling the rotational speed of the digital disk 1 rotates the digital disk 1 at the rotational speed answering to the read speed later then the prescribed read speed when the vibration detective signal 34 is outputted from the vibration detection part 4 when the digital disk 1 is rotated at the rotational speed answering to the prescribed read speed.