A method of manufacturing a rotary driving device is disclosed. The method includes the steps of: mounting a turntable, which is equipped with an anti-slipping section on a disc-placeable surface, to a rotary shaft; rotating the turntable; and shaving off a disc-contact surface, with which a disc contacts when the disc is placed, of the anti-slipping section with a cutting tool through a cutting off machining method from outside of the disc-placeable surface toward the rotary shaft. A cutting edge of the cutting tool is placed widthwise in parallel with an end face of the anti-slipping section and thickness-wise along an axial direction of the rotary shaft. The cutting edge is set such that the sections of the tool other than the cutting edge do not touch the anti-slipping section.