The present invention provides a machine tool making it possible to: feed a cutting tool in the machining direction, on the basis of conditions set by a user, while causing the tool to vibrate in a reciprocating manner along the machining direction; and cut a workpiece smoothly while segmenting the chips. The present invention also provides a control device for the machine tool. A machine tool (100) provided with setting means (C1, C2) and a correcting means (C1), and a device (C) for controlling the machine tool (100). The setting means (C1, C2) set the values of two parameters, the parameters being the number of relative rotations when the workpiece is machined, the number of reciprocating vibrations per relative rotation, and the vibration frequency that results from the period over which an operation command can be issued by the control device (C). The correcting means (C1) sets the one unset parameter to a prescribed value on the basis of the values set for the two parameters, and corrects the values of the two set parameters to prescribed values on the basis of the value set for the one unset parameter.