Neurodegenerative diseases are characterized by pathological changes, neuronal loss and gliosis. These disease involved changes of neurotransmitter in central nervous system. In Alzheimer's disease, cholinergic neurons were depleted. In Parkinson's disease(PD), while several kinds of mediator were affected, dopaminergic neurons were mainly associated with motor and non-motor symptoms. Antipsychotic drugs may induce worsening of parkinsonism and neuroleptic malignant syndrome in PD and dementia Lewy bodies(DLB). Therefore, it is recommended to use atypical antipsychotic drugs, especially quetiapine, for treatment of psychosis in PD and DLB.