方法：采取分层随机整群抽样法，抽取3 869名学生7 738眼进行视力检查。按照视力低下诊断标准，将所有观察对象分为正常、轻度、中度、重度视力低下，所有数据均用EpiData 3.1建立数据库及SPSS 18.0进行统计分析。

结果：西安市中小学生视力低下率为54.9%，以重度视力低下为主，随着年龄及年级的增长视力低下率明显呈上升趋势，女生视力低下率明显高于男生(χ²=63.19，P<0.01)。城市学生视力低下率显著高于农村学生(χ²=547.53，P<0.01)。

结论：西安市中小学生视力低下率较高，应及早采取有效措施以预防中小学生视力低下，降低和控制视力低下的发病率。

METHODS: Eyesight test was performed among 3 869 students(7 738 eyes)which were selected by multistage sampling. According to the diagnosis criterion of eyesight dysfunction, the students were classified as normal, slight, moderate, and severe group. The data were inputted into a database set up by EpiData 3.1 and analyzed by SPSS 18.0.

RESULTS: The rate of eyesight dysfunction among primary and secondary school students in the city of Xi'an was 54.9%,and most students were with severe eyesight dysfunction. The rate increased with the age and grade, the rate of girls was significantly higher than that of boys(χ²=63.19, P<0.01). The rate of students of urban was significantly higher than that of rural(χ²=547.53, P<0.01).

CONCLUSION: The prevalence of eyesight dysfunction is still apparent in primary and secondary school students in the city of Xi'an. Effective measures should be implemented to prevent and reduce the incidence of eyesight dysfunction.