Abstract: Objective To investigate the correlation between overweight and obesity among primary school students in Pudong New Area of Shanghai City and their health knowledge,attitude,practice（KAP）,in order to provide reference for preventing the occurrence and progression of overweight and obesity among primary school students and carrying out healthy education. Methods A urban and rural stratified cluster sampling method was used to select 1 236 students from grades 1 to 5 of two primary school in urban and rural areas of Pudong New Area of Shanghai in March 2022 for height and weight measurement. According to WS/T586-2018 "Screening Standards for Overweight and Obesity in School Age Children and Adolescents",473 overweight and obese students were screened. With informed consent,419 overweight and obese students underwent body composition analysis,waist and hip circumference,blood pressure,vital capacity,and other body shape and physical fitness testing indicators,as well as a questionnaire survey. Spearman rank correlation analysis was used to investigate the correlation between KAP and body mass index（BMI）. Results The detection rates of overweight and obesity in the two primary schools were 17.9% and 20.4%,respectively. Among them,the detection rates of overweight and obesity in boys were 20.5% and 25.8%,respectively,and the detection rates of overweight and obesity in girls were 14.8% and 14.1%,respectively. BMI,waist circumference,and waist height ratio showed statistically significant differences among different grades and genders（all P<0.05）,while body fat percentage showed statistically significant differences among different grades（P<0.05）,and there was no statistically significant difference among different genders（P>0.05）. There was a positive correlation between BMI and body fat percentage in overweight and obese children（r=0.702,P<0.05）.The total score of nutritional KAP for overweight and obese children was 36 points,with an average score of 24.75 points. There were statistically significant differences in health knowledge and total KAP scores among different grades（both P<0.05）,while there were no statistically significant differences in health attitudes and behaviors among different grades and genders（all P>0.05）. There was a negative correlation between KAP and BMI（r=-0.098,P<0.05）. Conclusion There is a certain correlation between KAP and overweight and obesity in primary school students. Improving dietary nutritional health education,as well as intervening in exercise behaviors,are an important measure to prevent overweight and obesity in primary school students.

Key words: Primary school students, Overweight, Obesity, KAP, Relevance