Objective To understand the dietary structure and nutritional characteristics of children aged 6-17 under the mode of collective feeding and self-catering in schools, and their effects on children's health-related indicators. Methods From January to April 2022, stratified sampling method was used to select 2 collective feeding schools and 2 non-feeding schools in Baoshan District of Shanghai City, and finally 1 538 school-age children aged 6-17 were selected. Then, the ^“3-day 24-hour dietary review method^” and ^“eighing method^” were used to carry out the survey, and combined with the ^“Chinese Residents' Balanced Diet Pagoda (2016)^” and ^“Chinese Residents' Dietary Nutrient Reference Intakes (DRIs 2013)^” standards to analyze the Food intake and energy supply ratio of the three major nutrients. At the same time, on-site sampling was conducted on the last day to collect samples of children's height, weight, blood pressure, blood, etc, and analyze the changes of students' obesity, anemia, blood lipids and other routinely available indicators. Results Compared with the school group feeding mode, the students in the self-dining mode had a higher rate of insufficient intake of cereals, potatoes and vegetables; and the latter students had a higher intake of aquatic products. high (P<0.05). At the same time, the daily intake of fat (79.9±8.4) g was higher, while the carbohydrate (243.1±21.4) g intake was relatively low in the self-catering mode. In addition, the health index measurement results showed that the rate of wasting (BMI<18.5) was 0.6%, the rate of obesity (BMI>28.0) was 3.8%, the rate of high TG was 7.3%, the rate of hypertension was 1.9%, and the rate of iron deficiency anemia was 2.6%, bone calcium loss rate was 2.8%, hyperglycemia rate was 5.1%. In addition, pearson correlation analysis showed that the intake of cereals and potatoes was positively correlated with BMI (r=0.348) and systolic blood pressure (r=0.438), and the intake of salt was also positively correlated with systolic blood pressure (r=0.472). ), while the intake of aquatic products was negatively correlated with the change of BMI value (r=-0.331). Conclusion Children aged 6-17 have insufficient intake of vegetables , aquatic products, soybeans and nuts in their diets. In addition, they need to pay attention to the intake of salt to prevent the occurrence of adverse health problems such as obesity and hyperlipidemia in children.