Renal diseases are often associated with hyperlipoproteinemia and dyslipoproteinemia. Total serum cholesterol and triglycerides are increased in nephrotic syndrome regardless of etiology. Approximately 40 to 50% of patients with renal insufficiency requiring hemodialysis show hypertriglyceridemia and dyslipoproteinemia. During chronic hemodialysis, high doses of unfractionated heparin deplete post-heparin lipolytic activity and aggravate dyslipoproteinemia. Hypercholestrolemia and hyperlipoproteinemia are often encountered in patients taking glucocorticoids and cyclosporin A after renal transplantation. Observations in experimental animals and in patients with genetically determined and acquired hyperlipidemias suggest that lipids can damage the kidney and lead to glomerulosclerosis. In vitro cell-culture studies of human glomerular cells have been useful in providing information on lipid-induced glomerular damage. Thus, there are strong indications that lipoproteins may play a critical role in the development of mesangial cell damage and progressive renal disease. Therapeutic measures that reduce and correct dyslipoproteinemia in renal disease may have long-term beneficial effects on the amelioration of renal disease.