The present disclosure relates to a mounting jig for manufacturing a tiling display device and a manufacturing method of a tiling display device using the same. A mounting jig for manufacturing a tiling display device according to an embodiment of the present disclosure includes: a supporting member; a plurality of jig magnets fixed to the supporting member; a hinge structure configured to rotate the plurality of jig magnets; and a guard rail rotating in response to rotation of the plurality of jig magnets and reducing damage caused during detachment or attachment. Therefore, when the mounting jig is attached to a display device, a safety distance can be secured by the guard rail disposed between the display device and the jig magnets and the mounting jig can be slowly attached to the display device without giving an impact to the display device.