The invention relates to the optical films, in particular to a quantum dot film applied to a backlight module. The quantum dot film aims to solve the problem that the color saturation of a liquid crystal displayer is poor. The novel quantum dot film comprises a quantum dot layer, and an upper waterproof layer and a lower waterproof layer are arranged on the upper surface of the quantum dot layer and the lower surface of the quantum dot layer respectively. The quantum dot layer comprises, by weight, 100 parts of adhesives, 5-20 parts of silica gel particles, 1-20 parts of diffusion particles and 0.1-20 parts of quantum dots. The surface of the silica gel particles is provided with a micropore structure. The quantum dots are adsorbed in micropores of the silica gel particles or dispersed in the adhesives. The silica gel particles and the diffusion particles are dispersed in the adhesives. The quantum dot film is applied to the backlight module and has the advantages of improving the color gamut and illuminance.