Nanomedicine has recently emerged as an exciting tool able to improve the early diagnosis and treatment of a variety of intractable or age-related brain disorders. The most relevant properties of nanomaterials are that they can be engineered in such a way that they can cross the blood brain barrier, with the final aim of targeting specific cells and molecules and to act as vehicles for drugs. Potentially beneficial properties of nanotherapeutics derived from its unique characteristics include improved efficacy, safety, sensitivity and personalization compared to conventional medicines. In this review, recent advances in available nanostructures and nanomaterials for brain applications will be described. Then, the latest nanotechnological applications for the treatment and diagnosis of neurological disorders, mainly brain tumors and neurodegenerative diseases, will be reviewed. Recent investigations of the neurotoxicity of the nanomaterial both in vitro and in vivo will be summarized. Finally, the ongoing challenges that have to be meet if new nanomedical products are to be put on the market will be discussed and some future directions will be outlined.