An electrode assembly manufacturing method comprising: a first process of manufacturing one type of basic unit sheets having a structure in which electrode materials (10, 30) and separator materials (20, 40), which are the same in number, are alternately stacked, or two or more types of basic unit sheets having a structure in which electrode materials (10, 30) and separator materials (20, 40), which are the same in number, are alternately stacked; a second-A process of cutting a portion of a margin area of the separator materials (20, 40), which is not covered with the electrode materials (10, 30), such that the separator materials (20, 40) of the basic unit sheets protrude over a specific distance from edges (12, 32) of the electrode materials (10, 30), and a process of forming an electrode assembly by repeatedly stacking unit structures formed by cutting the one type of the basic unit sheets at regular intervals, or by stacking, in a predetermined order, two or more types of unit structures formed by cutting each of the two or more types of the basic unit sheets at regular intervals, wherein the one type of the basic unit sheets have a four-layer structure formed by sequentially stacking a first electrode material, a first separator material, a second electrode material, and a second separator material, or a structure formed by repeatedly stacking the four-layer structure, and the two or more types of the basic unit sheets are stacked one by one in a predetermined order to form the four-layer structure or a structure formed by repeatedly stacking the four-layer structure, and characterized in that in the second-A process, the separator materials (20, 40) are held between a upper mold and a lower mold of a mold cutter, pressure is applied by the upper mold and the lower mold to the separator materials (20, 40) so as to attach edges of the separator materials (20, 40), and then the portion of the margin area of the separator materials (20, 40) fixed and held by the upper mold and the lower mold of the mold cutter is cut by using a cutting block. a first process of manufacturing one type of basic unit sheets having a structure in which electrode materials (10, 30) and separator materials (20, 40), which are the same in number, are alternately stacked, or two or more types of basic unit sheets having a structure in which electrode materials (10, 30) and separator materials (20, 40), which are the same in number, are alternately stacked; a second-A process of cutting a portion of a margin area of the separator materials (20, 40), which is not covered with the electrode materials (10, 30), such that the separator materials (20, 40) of the basic unit sheets protrude over a specific distance from edges (12, 32) of the electrode materials (10, 30), and a process of forming an electrode assembly by repeatedly stacking unit structures formed by cutting the one type of the basic unit sheets at regular intervals, or by stacking, in a predetermined order, two or more types of unit structures formed by cutting each of the two or more types of the basic unit sheets at regular intervals, wherein the one type of the basic unit sheets have a four-layer structure formed by sequentially stacking a first electrode material, a first separator material, a second electrode material, and a second separator material, or a structure formed by repeatedly stacking the four-layer structure, and the two or more types of the basic unit sheets are stacked one by one in a predetermined order to form the four-layer structure or a structure formed by repeatedly stacking the four-layer structure, and characterized in that in the second-A process, the separator materials (20, 40) are held between a upper mold and a lower mold of a mold cutter, pressure is applied by the upper mold and the lower mold to the separator materials (20, 40) so as to attach edges of the separator materials (20, 40), and then the portion of the margin area of the separator materials (20, 40) fixed and held by the upper mold and the lower mold of the mold cutter is cut by using a cutting block.