Objective: To discuss the clinical value of neck circumference in screening for overweight and obesity in children and adolescents, so as to provide a theoretical basis and new ideas for overweight and obesity screening. Methods: From May to July 2023, a total of 2 493 children and adolescents aged 3 to 16 were sampled from three schools by the cluster random sampling method. General data, neck circumference, body mass index (BMI), waisttoheight ratio, and other information were collected. Mann-Whitney ranksum test, Spearman correlation analysis, and receiver operating characteristic (ROC) curve analysis were used to statistically analyze the data. Results: The prevalence of overweight and obesity in children and adolescents aged 3 to 16 was 33.05%, and the prevalence of abdominal obesity was 28.33%.The neck circumferences of boys and girls in the overweight and obese group showed statistically significant differences from the normal weight group during the preschool, schoolage, and adolescence periods (Z=-16.69--4.54, P<0.05). The neck circumferences of children of different genders were moderately positively correlated with BMI (r=0.50-0.79, P<0.01). ROC curve analysis showed that neck circumference had good accuracy in assisting the screening for the occurrence of overweight and obesity in boys and girls during the preschool, schoolage, and adolescence periods [the AUC for boys:0.80(0.71-0.89), 0.89(0.86-0.91), 0.84(0.81-0.87); the AUC for girls:0.76(0.67-0.86), 0.81(0.74-0.88), 0.73(0.68-0.77), P<0.01], the optimal neck circumference cutoff values for boys were 26.95, 28.95, 33.55 cm, and for girls were 25.05, 26.55, 28.35 cm respectively. The neck circumferences of boys and girls were moderately positively correlated with the waisttoheight ratio during the schoolage and adolescence periods (r=0.41-0.70, P<0.01). ROC curves showed that neck circumferences had good accuracy in assisting the screening for the occurrence of abdominal obesity in boys and girls during the schoolage and adolescence periods [the AUC for boys:0.89(0.86-0.92), 0.82(0.78-0.85); the AUC for girls:0.84(0.75-0.93), 0.87(0.75-0.93)], the optimal cutoff values for boys were 28.95, 32.75 cm; for girls were 26.45, 31.85 cm respectively. Conclusion The neck circumference can be applied to screen for overweight and abdominal obesity in children and adolescents, and can provide new ideas for the prevention and control of overweight and obesity in children and adolescents.