AIM: To evaluate the poor vision condition and analyze the myopia etiological factor in primary school He'xi district of Sanya.

METHODS: A cohort of 1 218 subjects were recruited randomly from grade 1～6 of two primary schools. Visual activity test, dioptroscopy and risk factor questionnaire were evaluated.

RESULTS: The prevalence of poor vision was 29.55%. The incidence of myopia increased with grade, and was significantly higher in girls than that in boys. The outdoor activity time of myopic pupil(7.25±5.35h/wk)was significantly lower than emmetropic pupil(11.86±6.65h/wk)(P<0.05). The usage of electronic product(TV, computater and cell phone)time of myopic pupil(13.36±8.35h/wk)was significantly higher than emmetropic pupil(7.75±5.83h/wk)(P<0.05).

CONCLUSION: The increase of myopia incidence is closely related with sparing outdoor activity and excess usage of electronic product.