Abstract: ObjectiveTo examine the nutrition status among middle school students in Chongqing city and to analyze its influencing factors for making nutrition intervention measures.MethodsThe height and weight were measured and a questionnaire survey on nutritional know ledge,attitude and behavior was conducted among 2 465 students aged 10-19 years selected with stratified cluster sampling.The influence factors of diet behavior were analyzed with logistic regression.ResultsAmong the students,4.46% had malnutrition and the prevalence of underw eight,overw eight,and obesity was 44.87%, 5.23%,and 8.44%,respectively.There was a significant difference in the nutrition status betw een the students of different gender(P<0.0001).The results of logistic regression show ed that age,gender,nation,liking sports or not,study time,the body shape,and the education of the father and mother were influencing factors of nutrition status with the odds ratios of 1.145,3.499,1.351,0.579,0.863,0.529,0.671 and 1.532,respectively.ConclusionThe rates of malnutrition and underw eight were higher and the rate of overw eight and obesity was lower compared with those of the previous years among middle school students in Chongqiong city.The key measure to prevent malnutrition and excess-nutrition among the students is the popularization of nutrition know ledge and the promotion of moderate physical exercise.