ELECTROMAGNETIC SHIELDING DEVICE AND WIRE HARNESS

An electromagnetic shielding device (1) includes a conductive sheet (3) that is a sheet-shaped flexible conductive member that can be deformed into a tube shape, and an outer edge portion coupling member (5) that keeps the conductive sheet (3) in a tube shape in a state in which a first outer edge portion (31) and a second outer edge portion (32) of four outer edge portions of the conductive sheet (3) are joined together, the second outer edge portion (32) being located on the side opposite to the first outer edge portion (31). For example, a parallel slit group (300) is formed in the conductive sheet (3), the parallel slit group being constituted by a plurality of slits (30) that extend in a direction that crosses a first direction from the first outer edge portion (31) toward the second outer edge portion (32) and that are lined up in the first direction.