Abstract: The onset and development of myopia is the result of multiple factors, including genetic and environmental interactions. This is evidenced by animal experiment. For example, form\|deprivation induced animal models of myopia showed that decreased form stimulation of retina and sclera could induce the elongation of the ocular axis. Optical defocus\|induced myopia model showed that young monkeys develop axial myopia after wearing -9.0 D contact lens for 3 months. Egr\|1 gene knockout chicken showed longer axial length than controls. Studies on young children, including form\|deprivation related observations and the development of myopia among children of different ages also demonstrated the impact of genetics and environmental factors on the occurrence and development of myopia. Epidemiological studies showed that environmental factors and social behavior, such as the degree of education, social\|economical status, reading habits, urbanization and outdoor activities are highly associated with the development of myopia. However, the biological mechanisms of how environmental factors affect the development of myopia remain controversial. Different studies showed variable contributions of environmental factors to the development of myopia. With the advancement of genome\|wide scan and linkage analysis and GWAS technologies, at least 14 genes and 40 more candidate genes were found to be closely associated with the occurrence of myopia, especially high\|myopia. However, the effect of these genes is not yet to be demonstrated in independent samples.  (Int Rev Ophthalmol, 2015, 39：134-139)