AIM:To study the visual acuity and refractive status of students pupils and middle school students in Shenzhen, and to provide a scientific basis for the prevention and control of myopia.

METHODS:A cluster sampling method was used to select five primary school students(6 737)and three junior middle school students(1 925)from Shenzhen. The visual acuity,anterior segment, fundus, eye position, and refractive status were measured. Information on associated factors for poor vision were also obtained using a questionaire. The risk factors of poor vision and the rate of myopia between grade or gender were analysed by Chi-square test.

RESULTS:The rate of poor vision was 67.0%. Female, family history of high myopia, long time of continuous look near, short time of outdoor activities were the main risk factors. The rate of emmetropia, hyperopia, astigmatism and myopia were 15.1%, 11.3%, 11.0% and 62.6% respectively. Emmetropia, hyperopia and astigmatism incidenece rate decreased with age growing, but myopia incidence rate was increased. There were significant differences between adjacent two grades in myopia(χ²=7.338-45.018, P<0.05)except the primary grade six and the junior grade one. There were significant differences between boys(61.0%)and girls(65.5%)in myopia(χ²=17.180, P<0.05).

CONCLUSION:The rate of poor vison is pretty high in students of Shenzhen aged between 5 to 16 years old, and myopia is the main reason. The development rate of myopia is increased with age. Early management of myopia may play an important role in controlling poor vision in students.