PURPOSE: To eliminate the need for running-in and to obtain the fine metallic structure of tooth surfaces by forming radial grooves from an axial center in teeth of the worm gear of a worm-wheel finishing rolling roll.

CONSTITUTION: The worm-wheel rolling tool 1 has radial grooves and teeth 5 from the axial core of worms in teeth of the worms. The grooves 4 shorten the contacting length between worm wheel teeth surfaces and the teeth of the worm- wheel rolling tool 1 to increase contacting surface pressure, thereby finishing the worm wheel in a short time. Rolled tooth surfaces have tooth surface roughness better than cutting work and the metallic structure of the tooth surfaces is fine and tolerant to pitching and wear.