There has been an explosion of interest in the use of biomass as a source of renewable energy and materials. Despite being the most available natural polymer on earth, it is only quite recently that cellulose has gained prominence as a nanostructured material, in the form of nanocellulose. This term covers the range of materials derived from cellulose with at least one dimension in the nanometer range. It mainly consists of chemically (cellulose nano- crystals – CNCs) or mechanically extracted nanoparticles (microfibrillated cellulose – MFC). After intensive research, several initiatives have emerged in the perspective of producing nanocel- lulose on a large scale. Nanocellulose-based materials are carbon- neutral, sustainable, recyclable and non-toxic. They thus have the potential to be truly green nanomaterials, with many useful and unexpected properties