A controller for controlling a synchronized operation of spindle and feed axes. A spindle-axis control section includes an initial-motion control section for accelerating a spindle axis from a starting position; a maximum-acceleration detecting section for detecting a maximum acceleration of the spindle axis during acceleration; a residual rotation-amount detecting section for detecting a residual rotation amount of the spindle axis; a current-speed detecting section for detecting a current speed of the spindle axis; a decelerating-motion control section for decelerating the spindle axis to reach an intermediate speed, after the acceleration; a positioning-motion control section for decelerating the spindle axis to reach the target position after reaching the intermediate speed; and a torque-command limiting section for limiting a fluctuation of a torque command of the position control, instructed to the spindle axis, to a predetermined range over a period until a predetermined elapse condition is satisfied after reaching the intermediate speed.