PURPOSE: To enable a gear-cum-shaft, heightened with the extent of concentricity between gear and shaft, to be rolled with one machine capable of operation from turning to rolling of gear profile, and enable unmanned operation.

CONSTITUTION: Some of two gear rolling tools 1 or more are symmetrically in a work spindle A of a numerically controlled lathe in a circumferential equi-dividing manner. A rotative driving part 2, imparting a relative rotation to the gear rolling tools 1 in the work spindle A for its rotation. In addition, a pressing drive part 4 is provided which shifts each of the gear rolling tools 1 as far as the specified value in the radial direction of a work 3. Also a control part 5 is provided which detects a turning angle of the work spindle A and imparts a specified relative rolling angle to the rotative drive part. With this constitution, since the gear rolling tools 1 roll the work 3 while pressing it from both sides in the radial direction, this work 3 will in no case deflect at all. A holding means for a free end of the work 3 becomes unnecessary and, what is more, any reprogramming attending on a change in length of the work is not needed, thus the promotion of unmanned operation is made achievable.