Visual hallucination (VH) is the most common psychiatric symptom in Parkinson's disease (PD), which is closely related to the impaired quality of life and adversely affects the prognosis of patients. However, its pathogenesis is not yet clear. VH has been found to have relationship with disturbance in brain structures, visual pathways and attention networks, as well as neurotransmitters and there is strong evidence to support these findings in epidemiology, histopathology, clinical features and so on. Based on the results of multi-disciplinary research at home and abroad, this paper is to discusses the pathogenesis of visual hallucination in PD.