A cosmetic sheet is provided which makes a discolored area of the skin less conspicuous, and a manufacturing method thereof is also provided. Further, an image processing device and an image processing method are provided for manufacturing said sheet. This cosmetic sheet is adhered to a discolored area of the skin. The cosmetic sheet is provided with: a thin film which is adhered on one side to the skin； a complementary color layer which is arranged on the other side of the thin film and which has a color tone in a complementary color relation to the color of the discolored area； a light scattering layer which is arranged on the complementary color layer and which contains a reflective material； and a coloring layer which is arranged on the light scattering layer and which contains a color material.<；u/>； <；u/>；
