Objective: To investigate the prevalence of overweight/obesity and its associations with sleep duration among children and adolescents aged 6-17 in Gansu Province, so as to formulate tailored prevention and control strategies and intervention measures. Methods: Using a multi stage stratified cluster random sampling method, a questionnaire survey and physical examination were conducted among 2 172 students aged 6-17 from 2 monitoring points in Gansu Province from May to July 2022. Using Chi square test to analyze the inter group differences in the detection rates of overweight and obesity and the composition of sleep duration, and using Logistic regression model to analyze the correlation between overweight and obesity and sleep duration. Results: The prevalence of overweight and obesity were 10.45% and 6.86%, respectively. The average sleep duration was ( 8.28 ±1.66)h/d. The detection rate of overweight was high among high school students aged 16-17 and those with sleep duration<8 h/d ( χ 2=12.51, 19.32, 14.96), while the detection rate of obesity was high among male and non residential students ( χ 2= 5.89 , 9.59)( P ＜0.05). For both boys and girls, the rates of overweight and obesity among primary school students increased with the decrease in sleep duration ( χ 2=38.84, 9.80, 19.61, 41.60, P <0.05). The rates of obesity in boys were higher than girls across varying sleep durations among the general population (sleep duration <8 h/d: 6.07%, 11.11%, 8~<9 h/d: 5.76%, 6.09 %, 9~<10 h/d: 6.02%, 8.19 %, ≥10 h/d: 4.04%, 6.90%). Multivariate Logistic regression analysis showed that insufficient sleep duration among primary school students was positively associated with the risk of overweight and obesity, and adequate sleep duration among high school students was negatively associated with the risk of overweight and obesity (sleep duration 8~<9 h/d: OR primary school students = 1.89 , 9~< 10 h/d: OR primary school students =1.54, 8~<9 h/d: OR high school students =0.30, P <0.05). Conclusions Insufficient sleep is a risk factor for overweight and obesity among primary and secondary school students at monitoring sites in Gansu Province. Prevention strategies and interventions should be developed for different populations to ensure adequate sleep duration and reduce the risk of overweight and obesity among primary and secondary school students.