Objective To investigate the ocular surface effects of different digital media experiences in Chinese elementary school students.Design Population-based cross-sectional study was used.Setting 14 randomly selected primary schools in Yuhuatai District, Nanjing, ChinaParticipants 2,694 students between 7 and 8-year-old.Outcome Measures Prevalence of and risk factors for different types of dry eye disease,and different digital media experience with different ocular signs.Results The prevalence of ‘symptomatic DED’ was 8.7% (95% CI 7.6% to 9.8%) and ‘definite DED’ prevalence rate was 5.5% (95% CI 4.7% to 6.4%). In multivariable logistic regression model, allergic conjunctivitis (OR=4.33, 95% CI (3.01 to 6.23), p