Neuronal intermediate filaments are the most prominent cytoskeleton component of adult neurons in both central and peripheral nervous system. They include neurofilament triplet proteins, peripherin, α-internexin, nestin, and synemin. Although it was initially thought that neuronal intermediate filaments serve a primarily structural function, it has since been demonstrated that they constitute a dynamic network involved in neuronal differentiation, axon outgrowth, and regeneration. Finally, they emerged as a primary cause of some neurodegenerative diseases. Here, we focus on the properties, function, and regulation of neuronal intermediate filaments as well as their relationship to different neurodegenerative diseases.