The present invention relates to a filter and a plasma display device thereof, and the plasma display device includes: a plasma display panel; an EMI shielding sheet, wherein shielding layers including three or more thin film layers are repeatedly stacked; and a sheet for protecting external light having a base unit of which one side is formed with a plurality of grooves and a plurality of pattern units formed inside the grooves of the base unit and having a different refractive index from that of the base unit.According to the present invention, it is possible to effectively realize black images and enhance bright room contrast by arranging the sheet for protecting external light, which maximally absorbs and protects external light from the outside, at the front of the display panel. At the same time, it is also possible to enhance electromagnetic wave shielding effect.