<p>A dressing device (DA) is comprised of a pad holding mechanism (10) for holding and rotating a grinding pad (15) having a doughnut disk-shaped pad surface (15a), a dressing tool (2) having a substantially rectangular dressing surface (3), and a dressing tool holding mechanism (1) for holding the dressing tool (2) with the dressing surface (3) opposed to the pad surface (15a) of the grinding pad (15) held and rotated by the pad holding mechanism (10). The dressing tool holding mechanism (1) abuts dressing tool (2) held therein against the pad surface (15a) to effect dressing with the widthwise centerline (L1) of the dressing surface (3) directed to extend radially of the pad surface (15a). This makes it possible to improve the flatness of the processed surface after dressing.</p>
