Obesity has been pointed out as an important cause of kidney diseases. Due to its close association with diabetes and hypertension, excess weight and obesity are important risk factors for chronic kidney disease (CKD). Obesity influences CKD development, among other factors, because it predisposes to diabetic nephropathy, hypertensive nephrosclerosis and focal and segmental glomerulosclerosis. Excess weight and obesity are associated with hemodynamic, structural and histological renal changes, in addition to metabolic and biochemical alterations that lead to kidney disease. Adipose tissue is dynamic and it is involved in the production of "adipokines", such as leptin, adiponectin, tumor necrosis factor-α, monocyte chemoattractant protein-1, transforming growth factor-β and angiotensin-II. A series of events is triggered by obesity, including insulin resistance, glucose intolerance, dyslipidemia, atherosclerosis and hypertension. There is evidence that obesity itself can lead to kidney disease development. Further studies are required to better understand the association between obesity and kidney disease.