To review recent advances in the epidemiology, pathophysiology, clinical features, and treatment of obesity-related kidney disease. Studies have confirmed that obesity is associated with increased risk of developing chronic kidney disease (CKD). This risk extends to those who are metabolically healthy, indicating that obesity per se contributes to CKD independent of the metabolic syndrome. Recent developments in the pathophysiology of obesity-related kidney disease indicate that chronic inflammation and abnormal lipid metabolism contribute to kidney cell injury. Children with severe obesity have increased prevalence of early kidney abnormalities, including albuminuria, decreased kidney function, and elevated biomarkers of early kidney injury. For these patients, bariatric surgery has emerged as a treatment option to consider. Longitudinal studies in children and adults have demonstrated that in patients with obesity-related kidney disease, kidney function and albuminuria improve following bariatric surgery. The injurious renal effects of obesity are present in childhood, although the natural history and clinical spectrum of obesity-related kidney disease in children are not known. In obese children with early kidney disease, identification of kidney injury, implementation of preventive strategies, and prompt treatment are essential to improving clinical outcomes.