NUMERICAL CONTROL DEVICE

To execute machining for a front surface while rotating a work and, at the same time, apply machining to an eccentric position on an end face, according to an embodiment of the present invention, an NC device includes an arc-superimposition-interpolation control unit configured to rotate a work rotating shaft based on a command of a base axis program for controlling rotation of the work rotating shaft while performing front surface machining using a first cutter holder and, at the same time, subject a second cutter holder to position control on a second machining route obtained by superimposing the rotation of the work rotating shaft on a first machining route based on a command of a superimposition axis program for performing position control for the second cutter holder.