Objective: To describe the current distribution of daily physical activity time among elementary and junior high school students in Beijing, and to analyze the influencing factors and pathways at the individual, family, school and community levels. Methods: Data were drawn upon from a cross-sectional investigation in Beijing in 2023, and a total of 3 157 elementary and junior high school students were included in the final analysis. Questionnaire was used to collect data on basic characteristics, overall and in-school physical activity time per day, the number of sports mastered, perceived physical activity benefits and barriers scales, perceived family, school, and community physical activity supportive environment scales. Log-binomial regression model was used to analyze the associations between physical activity time and influencing factors, and structural equation modeling was used for the path analysis of the influencing factors. Results: The reported rates of ≥2 hours of overall physical activity per day and ≥1 hour of physical activity in school per day among elementary and junior high school students in Beijing in 2023 were 33.1% and 64.8%, respectively. The associations between the number of sports mastered by students and the reported rate of ≥2 hours of overall physical activity per day showed a typical dose-response relationship (P-trend<0.001). The perceived physical activity benefits-to-barriers ratio (PR=1.24, 95%CI: 1.20-1.28), scores of perceived family, school, and community physical acti-vity supportive environment scales were all positively associated with the reported rate of ≥2 hours of overall physical activity per day (PR=1.51, 95%CI: 1.38-1.66; PR=1.50, 95%CI: 1.37-1.64; PR=1.21, 95%CI: 1.16-1.27). The structural equation modeling showed that the number of sports mastered by the students (β=0.11, P<0.001), perceived physical activity benefits-to-barriers ratios (β=0.15, P<0.001), and scores of supportive environment scales consisting of family, school, and community (β=0.13, P<0.001) were associated with the reported rates of ≥2 hours of overall physical activity per day directly. In addition, the scores of supportive environment scales could indirectly influence the reported rates of ≥2 hours of overall physical activity per day by influencing the number of sports mastered by the students (β=0.21, P<0.001) and the perceived physical activity benefits-to-barriers ratio (β=0.56, P<0.001), while the number of sports mastered by the students could indirectly influence the reported rates of ≥2 hours of overall physical activity per day by influencing the perceived physical activity benefits-to-barriers ratios (β=0.05, P=0.003). The influencing factors and pathways of the reported rates of ≥1 hour of physical activity in school per day were similar with those of the reported rates of ≥2 hours of overall physical activity per day described above. Conclusion: The daily physical activity time among elementary and junior high school students in Beijing in 2023 fell short of meeting the national requirement. There was a need to build a supportive environment consisting of family, school, and community for physical activity, to promote the students ' sports skills, to establish the idea of independent physical activity, and to ensure that primary and secondary school students were given one hour of physical activity time every day, both inside and outside the school.