Magnetoplasmonics relates the plasmonic behavior with the magnetic film, and it makes very interesting for applications since it can produce to more sensitive sensors and can bring to active plasmonic devices. This work studies two systems to improve the magnetoplasmonic properties of Au and Co thin film. Optical and magneto-optical properties are analyzed by the effect of different concentrations of Co (or Au) nanoparticles (NPs) in Au (or Co) matrix. The morphological characterization of the NPs is determined by atomic force microscopy (AFM) using NEXT-TIP probes. Interface effects surrounding the NPs show an increase of the effective diameter compared to the real diameter. Optical properties of the Au NPs change compared to those of bulk material. Besides, the magneto-optical constants values of both systems are reduced than expected and it could be related to interface effects due to the strong hybridization occurs between Co and Au atoms.