目的：了解长沙市开福区小学生超重、肥胖情况及单纯性肥胖的影响因素，为小学生肥胖的防治工作提供科学依据。方法：随机抽取长沙市开福区7~12周岁小学生4 140名，按照体重指数(BMI)法判定出单纯性肥胖，将肥胖和正常儿童设为肥胖组和对照组，对影响小学生肥胖的有关因素进行分析。结果：①长沙市开福区小学生超重及肥胖检出率分别为9.76%和7.39%，男女生肥胖率分别为9.37%和5.13%。②与正常小学生相比，肥胖小学生的BMI，腰围(WC)，腰臀比(WHR)，体脂百分比(%BF)，收缩压(SBP)，血清甘油三酯(TG)和低密度脂蛋白胆固醇(LDL-C)明显升高，高密度脂蛋白胆固醇(HDL-C)明显降低。③肥胖小学生的WC，WHR与TG，LDL-C的偏相关系数大于BMI，%BF与其的偏相关系数。④儿童肥胖的危险因素可归结为常暴饮暴食、看电视时间长、进餐速度快、常吃油腻食物，而喜欢运动、运动时间长具有保护作用。结论：长沙市开福区小学生肥胖的发生率在国内处于高水平，控制儿童肥胖有助于慢性疾病的早期预防，预防儿童肥胖关键在于普及营养保健知识、注意平衡膳食和增加体力活动。

OBJECTIVE: To study the prevalence of obesity and the influencing factors for obesity in primary school students from Kaifu District of Changsha City. METHODS: A total of 4 140 students aged 7 to 12 years sampled randomly from Kaifu District of Changsha City were enrolled. Obesity was identified based on the body mass index (BMI). The influencing factors for obesity were investigated by non-logistic regression analysis. RESULTS: The prevalence of overweight and obesity were 9.76% and 7.39% respectively, and the prevalence of obesity in boys and girls were 9.37% and 5.13% respectively (P<0.05). The obese children had significantly higher BMI, waist circumference (WC), waist to hip ratio(WHR), percentage of body fat (%BF), systolic blood pressure, and serum triglyceride (TG) and low density lipoprotein-cholesterol (LDL-C) levels but significantly lower serum high density lipoproteincholesterol (HDL-C) level compared with the children with normal weight. BMI, %BF, WC and WHR were all positively correlated to serum levels of TG and LDL-C in obese children. Binge overeating, increased television viewing time, fast speed of eating and increased consumption of fried foods are all risk factors for the development of obesity. Preference for physical activity and sufficient physical activity were protective factors for obesity. CONCLUSIONS: The prevalence of obesity of primary school students from Kaifu District of Changsha City is high in China. The development of childhood obesity is associated with poor eating behaviors, less physical activity and increased television viewing time. The control of childhood obesity may be beneficial to early prevention of some adult chronic diseases.