AIM:To learn the current situation of teenagers’ eyesight and discuss the influence factors of vision loss so as so promote the work of better visual acuity protection and myopia prevention in teenagers.METHODS:An investigation on the eyesight,myopia and related factors of 2480 teenagers was conducted in Lianyungang city from May to August in 2009.Different grade student vision changes were analyzed,and family history,reading and surfing harmful habits with grouping antitheses were compared.RESULTS:The grade of the students was negatively correlated with the vision(r=-0.98),while positively correlated with myopia rate(r=0.985).On the aspect of history,reading and surfing harmful habit,the proportion of number in the myopia group was higher than that in the emmetropia group.CONCLUSION:The eyesight of teenagers declines as their grades become higher,while the myopia rate rises.History,reading and surfing harmful habit may be parts of the reasons for visual acuity declining;The unstability of tear films possibly correlates with the myopia rate.Correlation between gender and eyesight was unseen in the survey.Among those influencing factors,surfing harmful habit has ranked the first.