Objective The relationship of waist circumference(WC),body mass index(BMI) with some major related diseases among Jiangyin adults was studied.Methods Multi-stage stratified cluster random sampling method was performed from November 2007 to January 2008,Residents of 537 households in 3 towns(streets),6 administrative villages(the RC) in Jiangyin City were surveyed by way of questionnaires and physical examination.Results The mean of BMI,over weight and obesity rate of the sample population was(23.00±0.19),29.8% and 8.4% respectively.The overweight and obesity proportion of male was higher than that of female.The central obesity rate was 47.27%(37.10% in male,47.56%,female),The rate of female with central obesity was higher than that of male.The rate of overweight and obesity increased with age.The rate of hypertension and high blood glucose in the two groups(overweight and obesity) was significantly higher than that of the normal group.Those with systemic overweight / obesity and central obesity had higher risk of having hypertension and diabetes.Conclusions The prevalence of overweight and obesity rate of the residents in Jiangyin City increased in recent years.The rate of BMI and WC had positive correlation with hyper tension and diabetes.Those with systemic overweight / obesity and central obesity had higher risk of having hypertension and diabetes.