This paper presents briefly the review of optical properties and the surface plasmon resonance effect of metal nanostructures. The optical properties of metallic nanostructures are figured out via the interaction of light and the metallic surface that causes the surface plasmon resonance effect. Surface plasmons (SPs) are coupled modes of electromagnetic field and free electrons in metal. In the metallic nanofilms, plasmon waves have the ability to spread along the interface of the metal and dielectric or radiate in the far-field. Contrary to the continuous metallic surface
the spherical metallic nanoparticles (colloidal particles) denote the powerful color due to the combination of absorption and scattering processes. In colloidal metallic nanoparticles, the distance is limited by the size of the particles, therefore, the surface plasmon of colloidal particles are not spread out as far as the metal films - the surface plasmons of spherical metallic nanoparticles is also known as the located plasmons. Plasmon resonance in metallic nanoparticles regulates scattering colors because the extinction coefficient of the metal particles depends on particle size.