Metals have always proved their nature as integral parts of the Earth's crus t, water, air and various ecosys tems. Rare metals are commonly used as enzyme cofactors and act to regulate the cell functions. The accumulation of metals in the brain indicates the important role of these subs tances in the nervous sys tem. The lack of these metals is associated with a variety of neurological diseases. On the other hand, enhancement of metal levels may lead to various harmful intracellular events, including oxidative s tress, mitochondrial dysfunction, DNA fragmentation, protein falsity, endoplasmic endothelial s tress, dis turbance in autophagy and induction of apoptosis. To date, adverse effects of metal imbalances with multiple human diseases, such as Alzheimer's disease, amyotrophic lateral sclerosis, autism spectrum disorders, Guillen-Barre disease, Persian Gulf War syndrome, Huntington's disease, multiple sclerosis, Parkinson's disease, and Wilson's disease, have been reported. The role of some of these metal ions, especially in brain function, is important, which led to the introduction of the term metalloneurochemis try to describe the s tudy of metallic ions in the nervous sys tem at the molecular level. Conclusion: Various metals play an important role in the regulation of multiple vital processes of neurons. Deficiency or elevated levels of any of these metals have harmful effects on the human nervous sys tem, which may contribute to different neurodegenerative diseases.