To alternately perform turning indexing of a turret and rotation of a rotary tool spindle by a single motor.

A moving plate 35 is fixed to a piston 3a of a turret clamping- unclamping cylinder 3 concentrically arranged with a turning central shaft 2 of a turret 6, and turret driving system first clutch changing levers 34A and 34B and a rotary tool driving system second clutch changing lever are swingingly arranged on an installing surface 1a of a tool post main body 1 through a support stand. Rebellious meshing operation is mutually performed so that a turret driving shaft system clutch 26 meshes by a first clutch changing lever at turret unclamping time and a rotary tool driving system clutch 29 meshes by a second clutch changing lever at turret clamping time by a movement of the moving plate at turret clamping-unclamping time, and turning indexing of the turret and rotation of a rotary tool spindle 12 are made possible by a single servomotor 23.