Disclosed are an electrode assembly manufacturing method including sequentially stacking a first electrode, a separator, and a second electrode on a separation film having a continuous length to form mono-cells, each of the first electrode, the separator, and the second electrode being cut to a predetermined size from a winding roll so as to have a discontinuous structure, bonding the stacked mono-cells using a lamination device, locating a bi-cell at a folding start part, from which folding starts, on the separation film so as to be spaced apart from the mono-cells by a distance for folding, and performing folding in one direction with the bi-cell as a beginning, whereby it is possible to immediately perform the folding process without a separate preparation process after the lamination process in order to simplify the electrode assembly production process, and an electrode assembly manufactured by the method.