To provide a polishing tool which hardly generates eccentric wear of a polishing wheel.

The polishing tool includes: a support plate 11; an annular polishing wheel mounting plate 14 supported in a lower part of the support plate through a connection member 12 and having an annular polishing wheel 13 mounted on a lower surface; and an ultrasonic vibrator 15 fixed on the polishing wheel mounting plate. The connection member has an annular connection section 12a having such a shape and arrangement to satisfy a relationship of formula (1) of 0.1≤W/L≤0.5, formula (2) of 0.3≤T/W≤10, formula (3) of L1/L≥1/4, and formula (4) of L2/L≥1/4, and the center of gravity in th width direction of the polishing wheel mounting plate for mounting the polishing wheel is located at a lower side of a zone between an outer peripheral edge and an inner peripheral edge of the annular connection section on an upper surface of the polishing wheel mounting device, wherein W and T respectively indicate the width and height of the annular connection section, L indicates the width of the annular polishing wheel device, L1 indicates the width at an outer peripheral side rather than the outer peripheral edge of the annular connection section of the annular polishing wheel mounting plate, and L2 indicates the width on an inner peripheral side rather than the inner peripheral edge of the annular connection section of the annular polishing wheel device.