Abstract: A system for loading and unloading a machine tool provides a loading unit having a loading unit chassis. Two fixing devices each have a fixing piece disposed on the machine tool and having a receiving section, and a mating piece mounted on the loading unit chassis and having a configuration for engagement with the receiving section. The fixing devices are disposed vertically displaced from one another permitting simultaneous engagement. A bearing structure has rollers and supports the loading unit chassis on a surface. The bearing structure is vertically displaceable relative to the loading unit chassis to permit lifting and lowering of the loading unit chassis for engagement and disengagement of the first and second fixing devices. In an embodiment the receiving sections are slots arranged in a bottom of each of the fixing pieces and the configuration of the mating pieces is an upwardly directed engagement member.