Objective: To investigate the association of poor vision with time spent in outdoor activity among students from primary and middle schools, as well as from universities in Guangzhou, so as to provide targeted scientific basis for prevention and control of low vision. Methods: According to the requirements of National Monitoring of Common Diseases and Health Risk Factors among Students Manual, a total of 2 908 students were selected in 1 urban area and 1 suburban county for monitoring and investigation in Guangzhou. Results: The poor vision rate was 69.2% among students in Guangzhou, with girls (74.4%) > boys (64.2%), suburban country (76.3%) > urban areas (54.1%), university (95.0%) > vocational high school (82.5%) > regular high school (81.1%) > junior high school (73.4%) > primary school (45.6%). With the exception of primary students, the severe poor vision has the largest proportion in each age group. The proportion of spending less than 1 or 2 h for outdoor activities per day: girls>boys, suburban country > urban area, university and regular high school are higher. The poor vision rate of students who spent <2 h(72.3%) for outdoor activities daily was higher than those spent ≥2 h(65.6%). Compared with students who spent ≥2 h/d for outdoor activities, those spent < 2 h/d were at 1.24 times risk of being low vision(OR=1.24, 95%CI=1.04-1.48), controlling for the available confounders. Conclusion Poor vision rate of students in Guangzhou is high, occurring mainly with severe impairment and in younger age, the daily outdoor activity time is low. Girls, students from suburban country and junior high school should be considered as the emphasis for prevention and control of low vision.