Retina is the only visible part of the central nervous system. Studies have shown that there are structural abnormalities of retina in neurodegenerative diseases such as Alzheimer disease （AD） and Parkinson disease （PD）， but the changes of retina in the two diseases may be different. In order to explore the value of retinal changes in the diagnosis and differential diagnosis of central nervous system degenerative diseases， we summarized the research on retinal markers of different neurodegenerative diseases in AD and PD.