A technology capable of improving the accuracy of true-circular machining while avoiding an occurrence of intermittent cutting. A control unit of a machine tool determines an intermediate center position (Pi) in the moving direction for each divided rotation angle (E) smaller than a single rotation of the spindle and an intermediate eccentric radius (ri) around the intermediate center position (Pi) according to an initial position (Po) of the cutting edge in contact with the workpiece in the moving direction, the eccentric center position (Pc), and the eccentric radius (rc) to keep the cutting edge in contact with the workpiece as the moving object moves in the moving direction within a predetermined maximum feed speed (F) until a true-circular machining around the eccentric center position (Pc) is complete on the workpiece.