Abstract: The present invention provides a double-side grinder capable of grinding double-sides of an aluminum disk highly efficiently and affording a ground aluminum disk free of end-face flaw and superior in both surface accuracy and dimensional accuracy while obviating the occurrence of grinding marks extending in different directions. A rough grinding mechanism having rough grinding wheels disposed opposedly to each other is mounted, a finish grinding mechanism having finish grinding wheels disposed opposedly to each other is mounted just after the rough grinding mechanism, and a belt-like carrier having a large number of pockets formed longitudinally of the carrier with aluminum disks engaged therein is passed between the rough grinding wheels and the finish grinding wheels, thereby allowing double-sides of each aluminum disk to be subjected to rough grinding and finish grinding in a continuous manner.