Nowadays, nanomedicine brings new opportunities for diagnosis and treatment through innovative combinations of materials structured at the nanoscale, biomolecules and physicochemical processes. If the intrinsic properties of nanomaterials appear of major importance in this new discipline, the functionalization of these nanotools with biomolecules improves both their biocompatibility and efficacy. This is the case of carbohydrate derivatives, natural or synthetic, which are increasingly being used in nanostructures for medical purposes. As in current medicine, sugars are used to mimic their physiological roles. Indeed, carbohydrates enhance the solubility and reduce the clearance of drugs. They are used to mask immunogenic components of nano-objects and escape the body defenses and finally facilitate the delivery to the target tissue. All these properties explain the growing importance of sugars in nanomedicine.