Abstract: L-type amino acid transporter 1 (LAT1) is highly expressed in brain, especially in brain microvessel endothelial cells, transporting large neutral amino acids (LNAAs) into the brain to maintain the normal function of central nervous system (CNS). Some CNS diseases are often associated with dyshomeostasis of amino acids in the brain and the alterations in the function and expression of brain LAT1. In addition, the altered function and expression of LAT1 may affect the balance of LAT1-mediated endogenous substances in the brain, which could promote or delay the progression of the disease. And the alteration would have an effect on efficacy or toxicity of its substrate drugs. The advances in research on the function and expression of LAT1 under CNS diseases are summarized in the paper, so as to provide insightful reference for further research of CNS diseases and the development of CNS drugs.