Parkinson disease（ PD） is a common neurodegenerative disease. The abnormity of extracellular microenvironment， as another important pathogenic factor apart from cell dysfunction and toxic action， has been gradually concerned. The leading edge therapy on extracellular dysfunction includes convection-enhanced delivery（ CED） and simple diffusion delivery（ SDD）. The efficiency and safety of SDD has been proved in many advanced studies. In this paper， we summed up studies on cerebral interstitial therapy. On this basis， we highlighted newly-developed application of SDD on PD treatment by domestic scholars.