Objective: To explore the independent and interactive effects of school green space exposure and outdoor activity duration on screening myopia among primary and secondary school students, so as to provide theoretical support for the prevention and control of screening myopia in children and adolescents. Methods: From September to November 2023, 117 487 primary and secondary school students from 497 schools were selected using a cluster random sampling method, covering 98 counties (cities, districts) in Jiangsu Province. Data on the students screening myopia status and associated health influencing factors were collected and analyzed. School green space exposure was quantified using the normalized difference vegetation index (NDVI), which was extracted with ArcGIS Pro software; meanwhile, information on students outdoor activity duration was gathered through self reported questionnaires. Multivariate Logistic regression was applied to assess the independent and interactive effects of green space exposure and outdoor activity duration on screening myopia among primary and secondary school students. Results: Univariate analysis showed that there were statistically significant differences in screening myopia detection rates among primary and secondary school students of different genders, NDVI groups, every outdoor activity duration, monitoring points, school stages, parents educational level, and whether they lived on campus or had parents with screening myopia ( χ 2=88.91-1 950.08, all P <0.05); as the school age and sedentary time increased, the detection rate of screening myopia in primary and secondary school students also increased ( χ 2 trend =8 410.15, 2 028.91, both P <0.05). Independent effects showed that compared to the low NDVI group, the medium and high NDVI groups had lower risks of screening myopia ( OR =0.93, 0.95, both P <0.05). Compared to those with outdoor activity duration<2 h/d, students with outdoor activity duration≥2 h/d had a lower risk of screening myopia ( OR =0.96, P <0.05). When stratified by school level, compared to the low NDVI group, the medium NDVI group had lower risks of screening myopia in primary and junior high schools (primary school: OR =0.91; junior high school: OR =0.88, both P <0.05). Compared to those with outdoor activity duration<2 h/d, junior high school students with outdoor activity duration≥2 h/d had a lower risk of screening myopia ( OR = 0.90, P <0.05). When stratified by monitoring site, urban primary and secondary school students in the medium and high NDVI groups and those with outdoor activity duration≥2 h/d had lower risks of screening myopia ( OR =0.92, 0.92, 0.93, all P <0.05). Interactive effects showed that when medium or high NDVI was combined with outdoor activity duration≥2 h/d, the risks of screening myopia among primary and secondary school students were lower (medium NDVI×≥2 h/d: OR =0.89; high NDVI×≥ 2 h/d : OR =0.89, both P <0.05), and the combined effect was superior to that of a single factor. Conclusion Green space exposure and outdoor activity duration have negative correlations with screening myopia among primary and secondary students, and the combined effect is better than that of a single factor.