A diffuse reflection material, comprising white scattering particles and an adhesive agent, wherein, the whiteness of the white scattering particles is greater than 85, and the white scattering particles comprise high reflection scattering particles with a whiteness of greater than 90, high refraction scattering particles with a refractive index of greater than or equal to 2.0, and high thermal conductivity scattering particles, wherein the high thermal conductivity scattering particles are boron nitrite and/or aluminum nitride, and the particle shape of the high thermal conductivity scattering particles is rod-like or flat, when the high thermal conductivity scattering particles are flat, the high thermal conductivity scattering particles have a length in the flat direction of 0.7 to 7 μm and a length in the thickness direction of 0.02 to 0.25 μm; and when the high thermal conductivity scattering particles are rod-like, the high thermal conductivity scattering particles have a length in the length direction of 0.7 to 7 μm and a length in the peripheral direction of 0.02 to 0.25 μm, the high reflection scattering particles with a whiteness greater than 90 and the high refraction scattering particles are spherical in shape; and preferably the high reflection scattering particles with a whiteness greater than 90 and the high refraction scattering particles have a radius from 0.2 to 0.5 μm, the white scattering particles comprise, based on parts by weight, 0.08 to 0.15 part of high reflection scattering particles with a whiteness greater than 90, 0.5 to 0.7 part of high refraction scattering particles, and 0.3 to 0.5 part of the high thermal conductivity scattering particles, a ratio by weight of the white scattering particles to the adhesive agent is from 0.88 to 1.15 : 1, wherein the whiteness refers to a degree to which a surface is white, and is expressed by a percentage of white content, in which magnesium oxide is used as standard whiteness 100, and is defined as standard reflective index 100%, wherein Blue-light whiteness of a sample is represented by a percentage of reflective index on a surface of a magnesium oxide standard plate irradiated with blue light; and three numerical values are obtained through measurement by using red, green, and blue color filters or three light sources, and averaged to obtain a trichroic whiteness, in which the measurement is carried out by an optoelectronic whiteness meter. the high reflection scattering particles with a whiteness greater than 90 and the high refraction scattering particles are spherical in shape; and preferably the high reflection scattering particles with a whiteness greater than 90 and the high refraction scattering particles have a radius from 0.2 to 0.5 μm, the white scattering particles comprise, based on parts by weight, 0.08 to 0.15 part of high reflection scattering particles with a whiteness greater than 90, 0.5 to 0.7 part of high refraction scattering particles, and 0.3 to 0.5 part of the high thermal conductivity scattering particles, a ratio by weight of the white scattering particles to the adhesive agent is from 0.88 to 1.15 : 1, wherein the whiteness refers to a degree to which a surface is white, and is expressed by a percentage of white content, in which magnesium oxide is used as standard whiteness 100, and is defined as standard reflective index 100%, wherein Blue-light whiteness of a sample is represented by a percentage of reflective index on a surface of a magnesium oxide standard plate irradiated with blue light; and three numerical values are obtained through measurement by using red, green, and blue color filters or three light sources, and averaged to obtain a trichroic whiteness, in which the measurement is carried out by an optoelectronic whiteness meter. <EOS>