ObjectiveTo determine the prevalence of and risk factors for overweight and obese among Chinese children and adolescents.MethodsThis analytical cross-sectional study included 16,640 children and adolescents aged 6–18 years across four provinces of China in 2016. Physical characteristics and responses to questionnaires were analyzed. Body Mass Index (BMI) and the prevalence of overweight and obesity were calculated.ResultsAmong children and adolescents, the overall prevalence of overweight and obesity in 2016 in four regions of China was 27.2% and 29.6%, respectively. Among different stages and sexes, the highest prevalence of obesity (15.8%) was observed in adolescent boys. From childhood to adolescence, the obesity rate among boys increased by 0.7% (from 15.1% to 15.8%), while the obesity rate among girls decreased by 0.9% (from 10.8% to 9.9%). Children and adolescents who were overweight or obese had significantly higher systolic blood pressures, larger waist circumferences and larger hip sizes than those with a normal BMI. Logistic regression analyses identified thirteen factors associated with overweight or obesity in children and adolescents.ConclusionsOur results indicate that the prevalence of overweight and obesity is high among children and adolescents, especially among male adolescents in four regions of China. A suitable intervention program should not only help parents understand the serious risk of childhood obesity but also, more importantly, help to encourage a healthy lifestyle among children and adolescents.