The kynurenine pathway and its metabolites play an important role in the pathophysiologic mechanisms of central nervous system diseases. A variety of neuroactive substances produced by this pathway have neurotoxic， neuroprotective， or immunomodulatory effects. Therefore， exploring the heterogeneity of the expression of the kynurenine pathway and metabolites is important for explaining the pathogenesis of central nervous system diseases associated with it， which can help in the diagnosis， treatment， prevention and control of the diseases. This paper reviews the association of the kynurenine pathway and metabolites with a variety of central nervous system diseases