Abstract: Myopia is a refractive error with a high prevalence rate globally, especially in China. Being a great health problem, myopia is prevalent among children and there is a trend that high myopia rate is rising significantly among young Chinese children nowadays. To date, myopia is the main cause of reduced vision among children and is relevant to retinal detachment, macular degeneration, cataract and glaucoma, which brought heavy economic and social burden. However, there are no effective measures to control myopia. In recent years, epidemiological investigations and basic researches have found that outdoor activity is a protective factor against myopia. This study overviews researches on the correlation between outdoor activity the incidence, prevalence and progression of myopia for providing knowledge on myopia prevention and control to the public.