PURPOSE: To make a cutting process machine tool and a laser processing machine composite, and provide a composite machine tool capable of performing a cutting process and a surface hardening process alternately to a subject work of a three-dimensional form.

CONSTITUTION: A processing main shaft 28 is of a hollow structure having a through passage 42, and it is rotated by drive of a main shaft motor and is movable in the direction of a Z-axis. A work table 22 is disposed under the processing main shaft 28 to be movable in the direction of an X-axis and a Y-axis. At a lower end of the processing main shaft 28, either of an arbor 40 holding a cutting tool and an arbor 46 having a laser beam converging lens 54 can be installed properly by a tool replacing means 58. A laser beam is thus buided from an upper end of the processing main shaft 28 to the through passage 42. The incidental direction of the laser beam is set to be parallel to the Z-axis by regulation of a mirror 50, so the laser beam can be radiated while it is moved in the direction of the Z-axis of the processing main shaft 28.