Optic neuritis(ON) is one of common neuro-ophthalmologic diseases which cause vision loss in young and middle-aged population. There are obvious differences in the incidence and the epidemiological characteristics among different countries and regions. A number of studies on ON have been carried out at home and abroad. In China, it is still lack of multi-center, prospective, large sample epidemiological studies so far. This paper reviews the epidemiological characteristics of ON through the related domestic and overseas literatures.