The invention discloses a novel metal film coated decorative sheet and an application thereof. The novel metal film coated decorative sheet comprises a substrate, wherein the surface of the substrateis coated with a coating, a metal film is attached to the surface of the coating, the metal film is coated with a colorful pattern, and a protective film is attached to the other side of the metal film. The metal film coated decorative sheet is high in strength, good in fracture resistance, good in weather resistance, good in environmental protection property, rich in pattern, full in surface, high in hardness, resistant to scratch, easy to clean, fireproof, damp-proof and the like, the metal film coated decorative sheet can be applied to different interior decoration scenes of a public placeor a home decoration situation in different structural modes, specifically, the interior decoration scenes comprise a room, a lobby, a bathroom, a kitchen or a specific environment place except for ceilings, floors and wall surfaces, and in particular, the most intractable seamless applications at present of a window sleeve, a door sleeve, an internal corner and an external corner are solved.