With the rapid development of the plateau economy and the increasing human activity on plateau, the plateau related diseases turned into a focus of social and medical attention, but it is also the main constraint on the development of plateau. High altitude retinopathy(HAR)as a kind of high altitude disease, showed mainly retinal vascular congestion, tortuosity, retinal hemorrhage and vitreous hemorrhage. The early effect of HAR showed a temporary visual impairment, long-term effect were irreversible visual impairment and eye complications. The prevention is the key point for HAR, so early diagnosis and timely treatment critical for a good prognosis. The technology of visual electrophysiological examination plays an important role in the diagnosis, differential diagnosis, prognosis, evaluation of therapeutic effect and objective assessment of the visual function, with its unique advantage. Electroretinogram(ERG)is an important part of the visual electrophysiology. As an objective examination method of retinal function, not only can ERG find the early changes of retinal function at high altitude, especially those without any clinical symptoms of HAR, but also ERG can dynamically observe the development and therapeutic effects of HAR.