Objective: To understand the prevalence and associated factors of spinal curvature in children and adolescents in the Yangtze River Delta Region and to provide reference and help for the prevention and intervention of spinal curvature in children and adolescents. Methods: From September to November 2021, 8 246 middle school students in Anhui, Jiangsu, Shanghai, and Zhejiang provinces in the Yangtze River Delta Region were selected by stratified cluster sampling for spinal curvature assessment and questionnaire survey. Results: The detection rate of spinal curvature in middle school students in the Yangtze River Delta was 8.46 %. Girls (9.82%) were significantly higher than boys (7.20%)( χ 2=18.25, P <0.01), and students from urban area (10.77%) was significantly higher than that of suburban area (4.94%)( χ 2=86.75, P <0.01). Junior high school students (6.65%) were significantly lower than high school students (10.34%)( χ 2=36.26, P <0.01). Logistic regression analysis showed that urban area( OR= 2.58, 95%CI =1.72-3.86), time usage of electronic equipment ≥ 3 h/d( OR=1.61, 95%CI =1.14-2.29), break between near work for more than 1 h ( OR=1.42, 95%CI =1.01-1.97) and outdoor activity <2 h/d( OR=1.84, 95%CI =1.26-2.69) were positively correlated with the occurrence of spinal curvature( P <0.05). Conclusion The detection rate of spinal curvature in middle school students in the Yangtze River Delta is relatively high, which is related to time spent on screen, near work and outdoor activity. Education and guidance should be strengthened to reduce the detection rate of spinal curvature.