This work comprehends a review of nanostructured materials employed in the fabrication of optical fiber sensors in the last years. The continuous advances in nanofabrication techniques have enabled to manipulate the matter precisely producing well defined nanostructurated coatings or repetitive patterns at nanoscale level. The interactions of light with these nano-organized materials or patterns at the nanoscale level enable to observe interesting phenomena, such as interferometry, fluorescence, absorbance, resonances and many others which can be exploited in the fabrication of sensing devices. A particular case consists of optical fiber sensors, where the light travelling through an optical fiber interacts with the sensitive layer. The properties of the sensitive layer, such as the organization, physical properties, chemical bounds etc. will determine the sensing characteristics of the final device. The utilization of some of the most common nanostructured materials, such as polymers, nanoparticles, metals, metal oxides or biological coatings are reviewed here.