Objective To explore the relationship between environmental selenium content and myopia among junior high school students.Methods A total of 600 junior high school students from selenium-rich， selenium-sufficient， and selenium-deficient areas from Enshi（200 from each area） were randomly selected. The prevalence of myopia， serum selenium， and hair selenium， as well as the glutathioneperoxidase （GSH-Px） and selenoprotein P （SEPP-1） and the selenium distributions of staple crops and drinking water， were determined. The z-test was used to compare continuous data between two groups， a one-way analysis of variance was used to compare continuous data between multiple groups， a chi-square test was used to compare the rates， and the Pearson correlation test was performed to investigate the correlation between selenium and myopia.Results All of the junior school students were divided into myopic （n=244， 40.67%） and non-myopic （n=356， 59.33%） groups. The levels of serum selenium， hair selenium， GSH-Px， and SEPP-1 in the selenium-deficient areas were significantly lower than those in the selenium-adequate areas and the selenium-rich areas ［（71.25 ± 10.31）μg/L vs.（86.74 ± 11.25）μg/L vs.（102.31 ± 10.26）μg/L，（0.56 ± 0.20）μg/g vs.（0.72 ± 0.11 ）μg/g vs.（0.81 ± 0.12）μg/g，（85.26 ± 15.16）μ/L vs.（95.34 ± 13.20）μ/L vs.（114.65 ± 12.12）μ/L，（7.41 ± 1.65）mg/L vs.（10.25 ± 2.47）mg/L vs.（12.36 ± 3.25）mg/L］ （F=9.65， 12.24， 10.32， 9.41， P<0.01）. Compared with the students in the selenium-deficient and selenium-adequate areas， myopic incidence of students in the selenium-rich areas was significantly reduced （χ²=28.29， P<0.01）. The selenium levels of drinking water and staple crops in the selenium-rich areas were significantly higher than those in the selenium-adequate and selenium-deficient areas （F=12.35， 5.36， P<0.01）. A negative correlation was observed between serum selenium and hair selenium and the myopic incidence （r=-0.542， -0.621， P<0.05）.Conclusion The higher the environmental selenium content in different areas of Enshi， the lower was the incidence of myopia in junior middle school students. A certain correlation was observed between selenium and myopia in junior middle school students.