Objective To investigate the potential complications of obesity in primary and secondary school students and the importance of early intervention. Method Height,weight,waist circumference,hip circumference,fat rate,fasting blood glucose,blood lipids,liver function,uric acid,insulin,postprandial glucose and insulin were detected in 247 cases of primary and secondary school students who participated in the training of obesity related knowledge voluntarily(136 cases were obese,55 were overweight,56 were normal),and all the children received pulmonary function test.The clinical data were analyzed. Results The incidence of hypertension,dyslipidemia,abnormal glucose metabolism,liver damage,hyperinsulinism and abnormal pulmonary function was 10.3%,38.2%,25.7%,22.1%,52.2%,51.5% and 56.6%,respectively. Conclusions Obese primary and secondary school students often suffer from potential complications such as hypertension,dyslipidemia,abnormal glucose metabolism,fatty liver,hyperuricemia,lung function damage.Therefore,obesity in primary and secondary school students should not be ignored,and the early intervention is very important.