To provide a stopper for a finger ring which has a simple and inexpensive construction and can be easily handled and wherein the ring can be surely prevented from rotating.

The stopper 1 for a finger ring has a rotary body 2 comprising an approximately cylindrical resin, and the stopper includes a hole 4 which extends axially through the body 2 so as to be offset from the center axis thereof and has an approximately circular cross section, and a slit 6 formed through the thinnest portion of the body 2 to bring the outer periphery of the body 2 into communication with the hole 4. The width of the slit at each of the opposite ends thereof is made larger than that of the central portion of the slit, thereby allowing a finger ring 10 to be easily inserted into the hole 4. For mounting the stopper 1 to the ring 10, the ring 10 is inserted into the hole 4 through the slit 6 and the body 2 is rotated to a predetermined position so that a thick wall portion of the body 2 is positioned between the ring 10 and a finger.