Neurodevelopmental disorders(NDDs)are chronic developmental brain disorders that can affect cognition,motor,social adaptation,behavior and so on due to multiple genetic or acquired causes.Natural polysaccharides are synthesized by living organisms,located in the cell wall,inside and between cells,and outside the cells,and are essential components of life activities.Previous studies have found that natural polysaccharides play an important role in neurological diseases,which mainly ameliorate the behavioral abnormalities and clinical symptoms caused by anti-oxidative stress,anti-neuronal apoptosis,anti-neuroinflammation,anti-excitatory amino acid toxicity,and regulation of the brain-gut axis.This review summarizes the intervention role of 17 bioactive polysaccharides from plants and fungi in neurological diseases,aiming to provide new ideas for the research and treatment of NDDs.