Present disclosure relates to a variable jig which is a jig device to manufacture a battery cell in which an electrode assembly is embedded in a battery case made of a laminate sheet including a resin layer and a metal layer, including a die assembly having an inwardly recessed structure corresponding to a storage configured to mount the electrode assembly located on the laminate sheet or a portion to be molded as the storage; and a fixing die configured to fix an outer periphery of the sheet in a normal position, wherein the die assembly is configured to allow adjustment of at least one of a width or a length of the inward recess according to a size of the electrode assembly.