Nosepiece for eyeglass frames, which comprises a plate, to which an appendage is fixed that is provided with a first through hole, and a cup which is provided with two second through holes and houses at its interior the appendage with the first through hole aligned with the second through holes. The nosepiece also comprises a screw having the stem inserted in the first through hole of the appendage and screwingly engaged in one of the second through holes of the cup. The screw is provided with an annular groove made on the stem, and the appendage comprises at least one retention tooth projecting into the first through hole and housed within the annular groove of the screw for the retaining of the latter.