The invention provides a device for automatically carrying in and out a workpiece cooperating with a tool spindle stock of a composite working lathe. The composite working lathe comprises a main spindle 10, a workpiece handling device 20 and a tool spindle stock 30 that rotates around a B axis. A workpiece carry-in/out device 100 comprises a frame 120 including a material carry-in hand 130 and a finished product tray 140, and a cylinder 110 for moving the frame back and forth. A door 60 of a cover 50 is opened to carry in a material B1 and carry out a finished product P1.