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Nanotechnology is the most prospective technology in the twenty-first century. Nanomaterials are increasingly applied in numerous fields due to their physical, chemical and biological properties which are different from conventional materials. Two principal factors cause the properties of nanomaterials to differ significantly from other materials: increased relative surface area and quantum effects. Nanomaterials applied in cosmetics include nano-ZnO and TiO2, fullerene, nanovesicles, nanoemulsions and nanoparticles. Nanomaterials have exhibited obvious benefits in the area of cosmetics, but attention should be paid to their safety.