PURPOSE: To efficiently grind a disk with simple constitution and with a high speed.

CONSTITUTION: This device is provided with a rotary pedestal 2 attaching a pair of spindles 1a, 1b driving to rotate the disk and while cramping the disk D, and the device is constituted so that the rotary pedestal 2 is rotated intermittently by 180 degree around a rotary shaft 3 between a disk receipt/ deliverly position 4 and a grind work position 5. The spindles 1 are driven to rotate at the grind work position 5. At the same time, a pair of grinding member 10 are arranged so as to hold the disk there between to the grind work position 5, and the disk is ground by pressing a grinding tape 13 in the grinding member 10 by a pressure roller 17 in the state of balancing load to the front and rear faces of the disk. Simultaneously, the worked disk D is unloaded and the disk D to be worked next is loaded to the spindle 1 placing in the disk receipt/deliverly position 4.