A winding electrode body is provided which includes a belt-shaped positive electrode, a belt-shaped negative electrode, and two belt-shaped separators. In the above winding electrode body, the two separators are laminated with the positive electrode and the negative electrode are wound in the state that positive electrode and the negative electrode are interleaved by the intermediate portions of the two separators in the longitudinal directions thereof, start edges of the two separators extending past the intermediate portions are disposed to face each other in a free edge state at a position at which the positive electrode and the negative electrode are not provided, and end edges of the two separators extending past the intermediate positions are disposed and fixed to each other at a position at which the positive electrode and the negative electrode are not provided.