Objective · To investigate the relationship between obesity and chronic kidney disease (CKD) in a community-based study among a middle-aged and elderly Chinese population.  Methods · A survey of 10 375 inhabitants aged 40 years or older in Jiading District of Shanghai was performed using cluster sampling. All the subjects were recruited to undergo questionnaire interview, anthropometric measurements, and biochemical measurements. Blood and urine samples were collected to measure biochemical features, including plasma glucose, lipid profiles, liver and renal function, as well as urinary albumin and creatinine. Obesity status was diagnosed according to the World Health Organization (WHO) criteria. According to body mass index (BMI) levels, the subjects were divided into normal weight group (BMI<25 kg/m2), overweight group
 (25 kg/m2 ≤ BMI<30 kg/m2) and obesity group (BMI ≥ 30 kg/m2). The estimated glomerular filtration rate (eGFR) was calculated based on American Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation. Logistic regression analysis was used to analyze the risk of CKD among people with different BMI levels.  Results · Increased BMI levels were associated with more unfavorable metabolic profiles. After a variety of factors were adjusted, each 1 kg/m2 increment of BMI was associated with a 9% higher risk of prevalent CKD, and the odds ratio (OR) was 1.09 (95% CI：1.07-1.12). Results from multivariate Logistic regression analysis showed that in the total population, compared with individuals in the normal weight group, those in the overweight and obesity groups had 51% (OR=1.51, 95% CI: 1.27-1.78) and 181% (OR=2.81, 95% CI: 2.20-3.61) higher risk of prevalent CKD.  Conclusion · In the middle-aged and elderly community population in China, overweight and obesity are associated with an increased risk of prevalent CKD.