Abstract: Objective To investigate the relationship between dietary knowledge levels and overweight/obesity among Chinese adolescents and to provide evidences for the prevention of overweight/obesity in the population.Methods Information on 1 942 adolescents aged 12 to 18 years in Guangxi,Guizhou,Jiangsu province and Shanghai,Beijing,Chongqing municipality were extracted from the datasets of four waves of China Health and Nutrition Survey in 2004,2006,2009,and 2011.The effect of dietary knowledge levels on overweight/obesity among the adolescents was assessed with logistic regression analysis and the main factors associated with dietary knowledge level were also explored using multiple linear regression.Results Among the adolescents,the overweight/obesity rate of the boys was higher than that of the girls (13.6% vs.8.1%) and the age-specific rate was the highest (17.1%) for those aged 12 years;for the adolescents with different household economic status,the overweight/obesity rate was the highest (14.3%) in those with high family income.The results of logistic regression showed that the adolescents with a high level of dietary knowledge was significantly less likely to have overweight/obesity (odds ratioOR=0.961,95% confidence interval95%CI:0.924-0.999,P=0.046).Multivariate linear regression revealed a significant positive correlation between the dietary knowledge level of the adolescents and their mothers (β=0.423,95%CI=0.361-0.484,P=0.000).Conclusion The occurrence of overweight and obesity could be reduced by increasing dietary knowledge level among adolescents and high dietary knowledge of the mothers can promote the dietary knowledge level of their children.