Disclosed is a low-cost rotary grinding tool with an excellent low-noise characteristic capable of suppressing noise during grinding. Specifically disclosed is a rotary grinding tool with an excellent low-noise characteristic, which comprises a grinding surface having a surface density of 20 particles/cm2 or more formed on at least a part of a surface of a metallic disc by brazing hard particles having a hardness of 9 or more on the Mohs scale; and an attachment portion to be attached to a rotatable shaft of a rotating device formed in a central portion of a holder that supports the metallic disc. The metallic disc and the holder are joined to each other.