Disclosed is a special-shaped light guide body covered with a photocatalyst optical film. The special-shaped light guide body comprises a transparent solid geometry and an optical film, and is characterized in that the outer surface, with a thickness greater than 1mm, of the transparent solid geometry is covered with the optical film; for the solid geometry, at least one outer surface is an incident surface and at least one outer surface is light emitting surface; and the solid geometry comprises at least one dielectric film material optical film of sub-micron or nano particles. The invention aims to cover a matched optical film by a known coating method for the outer surfaces, with different optical functions, of the solid geometry, so as to make a light guide body with higher efficiency and more functions possible. The light guide body can not only be used in cooperation with both a led light source and other various light sources in lighting, display lighting and backlighting, but can also be made into purification lamps, germicidal lamps, phototherapy lamps, plant lighting fixtures and the like. With the development of electronic thin film technology, more opportunities will open up to applications of the light guide body.